3300 ACM Installation & Operation Manual - apc.com · 3300 ACM Installation and Operation Manual Power Measurement Ltd. iv Table of Contents 3.5 Selecting Direct or PT Input & Setting

3300 ACMEconomical DigitalPower Meter/Transducer

CONTENTS

Installation& OperationManual

DangerDuring normal operation of this device, hazardous voltages are present whichcan cause severe injury or death. These voltages are present on the terminalstrips of the device and throughout the connected potential transformer (PT),current transformer (CT), status input, relay, and control power circuits. Installa-tion and servicing should be performed only by qualified, properly trainedpersonnel. See Chapter 2: Installation for additional warnings.

WarningThis equipment generates, uses, and can radiate radio frequency energy and ifnot installed and used in accordance with the instructions manual, may causeinterference to radio communications. It has been tested and found to complywith the limits for a Class A computing device pursuant to Part 15 of FCC Rules,which are designed to provide reasonable protection against such interferencewhen operated in a commercial environment. Operation of this equipment in aresidential area may cause interference in which case the operator will berequired to take whatever measures may be required to correct the interference.

Limitation of LiabilityPower Measurement Limited reserves the right to make changes in the devicesor the device specifications identified in this Installation and Operation Manualwithout notice. Power Measurement Limited advises customers to obtain thelatest version of device specifications before placing orders to verify that theinformation being relied upon by the customer is current.

In the absence of written agreement to the contrary Power MeasurementLimited assumes no liability for Power Measurement Limited applicationsassistance, customer’s system design, or infringement of patents or copyrights ofthird parties by or arising from the use of devices described herein. Nor doesPower Measurement Limited warrant or represent that any license, eitherexpressed or implied, is granted under any patent right, copyright, or otherintellectual property right of Power Measurement Limited covering or relatingto any combination, machine, or process in which such device might be used.

EXCEPT TO THE EXTENT PROHIBITED BY APPLICABLE LAW, UNDER NOCIRCUMSTANCES SHALL POWER MEASUREMENT LIMITED BE LIABLE FORCONSEQUENTIAL DAMAGES SUSTAINED IN CONNECTION WITH SAIDPRODUCT AND POWER MEASUREMENT LIMITED NEITHER ASSUMES NORAUTHORIZES ANY REPRESENTATIVE OR OTHER PERSON TO ASSUME FORIT ANY OBLIGATION OR LIABILITY OTHER THAN SUCH AS IS EXPRESSLYSET FORTH HEREIN.

3300 ACM is a trade mark of Power Measurement Limited. Other brands andtheir products are trade marks of their respective holders and should be noted assuch.

© 1999 Power Measurement Ltd.The information contained in this document is believed to beaccurate at the time of publication, however, Power MeasurementLtd. assumes no responsibility for any errors which may appearhere and reserves the right to make changes without notice.

Toll Free1-877-METER-IT(1-877-638-3748)

World-Wide Web www.pml.com

Worldwide Headquarters

P O W E R M E A S U R E M E N T L T D .

2195 Keating Cross Road,Saanichton, BC,Canada V8M 2A5Tel: 1-250-652-7100Fax: 1-250-652-0411

Europe & Middle East

P O W E R M E A S U R E M E N T E U R O P E

Zaventem Business Park, Ikaroslaan 5,B-1930 Zaventem(Brussels), BelgiumTel: 32-2-720-19-19Fax: 32-2-720-95-86

Asia & Pacific

P O W E R M E A S U R E M E N T

A U S T R A L I A

7/16 Ledgar Road,Balcatta, PerthWestern Australia 6021Tel: 61-89-345-3866Fax: 61-89-345-3899

Revision Date: February 1, 1999© 1999 Power Measurement Ltd.All rights reservedPrinted in Canada70000-0012

For further information or technical assistance, pleasecontact your local Power Measurement representative,or Customer Service at one of the following locations:

ISO 9002-94Reg i s t r a t i on

Cert # 002188

3300 ACM Installation and Operation Manual Power Measurement Ltd.

ii

Throughout this operation manual, the following methods are used to highlight importantinformation:

NOTEDescribes important considerations related to a device setup, feature or application.

CAUTIONAlerts you to a condition which could potentially cause damage to the device or other externalequipment.

WARNING or DANGERWarns you to avoid conditions that could potentially cause serious personal injury and/orequipment damage.

CONVENTIONS


iii

Table of Contents

1 INTRODUCTION

1.1 Description .............................................................................................................. 1-1

1.2 System Applications ............................................................................................... 1-2

2 INSTALLATION

2.1 Location & Mounting ................................................................................................ 2-1

2.2 General Wiring Considerations ................................................................................ 2-2

2.3 Power Supply Connections ...................................................................................... 2-2

2.4 Chassis Ground Connection .................................................................................... 2-3

2.5 Phase Voltage and Phase Current Input Connections ............................................. 2-32.5.1 Phase Voltage Inputs .............................................................................. 2-32.5.2 Phase Current Inputs ............................................................................... 2-42.5.3 PT & CT Connection ............................................................................... 2-42.5.4 Connections for 3-Phase Wye (Star) Systems ........................................ 2-52.5.5 Connections for 3-Phase Delta Systems ................................................. 2-92.5.6 Connections for Single Phase Systems ................................................ 2-11

2.6 Communications Connections ............................................................................... 2-12

2.7 kWh Pulse Output ................................................................................................. 2-16

2.8 Maintenance .......................................................................................................... 2-16

2.9 Field Service Considerations ................................................................................. 2-17

3 GENERAL OPERATION

3.1 Introduction ............................................................................................................. 3-1

3.2 Power Up ................................................................................................................. 3-1

3.3 Display Mode .......................................................................................................... 3-23.3.1 Front Panel Display ................................................................................. 3-23.3.2 Front Panel Buttons ................................................................................ 3-33.3.3 Function Button ....................................................................................... 3-4

3.4 Field Programming .................................................................................................. 3-53.4.1 Introduction ............................................................................................. 3-53.4.2 Entering Programming Mode ................................................................... 3-53.4.3 Programming Button Functions ............................................................... 3-53.4.4 Entering and Changing the Password ...................................................... 3-63.4.5 Accessing and Modifying Parameters ..................................................... 3-63.4.6 Operating Parameter Descriptions ........................................................... 3-8

3.5 Selecting Direct or PT Input & Setting PT Scales, Amps Scale, and Volts Mode . 3-10


iv

Table of Contents

3.5 Selecting Direct or PT Input & Setting PT Scales, Amps Scale, and Volts Mode . 3-10

3.6 Display Format ...................................................................................................... 3-113.6.1 Choosing a Display Format ................................................................... 3-113.6.2 High-Resolution Display Option ............................................................. 3-11

3.7 Adjusting the Display Contrast .............................................................................. 3-11

3.8 Using the kWh Pulse Output Function ................................................................... 3-12

3.9 Using the Diagnostic Parameters .......................................................................... 3-12

4 MEASURED PARAMETERS

4.1 Introduction ............................................................................................................. 4-1

4.2 Parameter Descriptions ........................................................................................... 4-44.2.1 Real-Time ................................................................................................ 4-44.2.2 Energy & Volt-Hours ................................................................................ 4-4

4.3 Measurement Modes ............................................................................................... 4-54.3.1 Demand ................................................................................................... 4-54.3.2 Minima/Maxima ....................................................................................... 4-74.3.3 Bi-Directional Energy ............................................................................... 4-74.3.4 Power Reading Polarities ......................................................................... 4-8

5 COMMUNICATIONS

5.1 Introduction ............................................................................................................. 5-1

5.2 RS-485 Communication ........................................................................................... 5-1

5.3 Setting the COM MODE, UNIT I.D. & BAUD RATE ................................................ 5-2

5.4 3300 ACM -TRAN Model Operation ......................................................................... 5-3

5.5 M-SCADA / L-SCADA ............................................................................................. 5-3

5.6 3300 RDT Remote Display Terminal ........................................................................ 5-4

5.7 Third Party System Compatibility ............................................................................ 5-4

5.8 Modicon Modbus Compatibility ................................................................................ 5-5

5.9 PLC/AB Compatibility .............................................................................................. 5-7


v

Appendices

A MECHANICAL & MOUNTING DIMENSIONS

Display Module ....................................................................................................... A-1

Base Module .......................................................................................................... A-2

B 3300 ACM FIRMWARE VERSIONS

C 3300 ACM TECHNICAL SPECIFICATIONS

Accuracy, Resolution, & Range.............................................................................. C-1

Input Ratings .......................................................................................................... C-1

D MODEL/ORDERING INFORMATION

E WARRANTY & REGISTRATION

1 Warranty ................................................................................................................. E-1

2 Product Return Procedure ...................................................................................... E-1

3 Registration ............................................................................................................ E-1

F TROUBLESHOOTING

G SERIAL COMMUNICATIONS PROTOCOL

1 Introduction ............................................................................................................ G-11.1 Purpose .................................................................................................. G-11.2 Revisions ............................................................................................... G-1

2 Detailed Description................................................................................................ G-12.1 Protocol Ground Rules ........................................................................... G-12.2 Description of the Packet Structure ........................................................ G-2

2.2.1 Message Establishment Field ................................................ G-22.2.2 Control Information Field ........................................................ G-22.2.3 Address Information Field ...................................................... G-22.2.4 Data Field ............................................................................... G-22.2.5 Message Termination Field .................................................... G-3

2.3 Broadcast Packets ................................................................................. G-32.4 Network Timing Considerations .............................................................. G-4

3 Packet Communications......................................................................................... G-53.1 Read Registers Packet ........................................................................... G-53.2 Write Registers Packet ........................................................................... G-7

4 Register List ........................................................................................................... G-7

5 Packet Examples ................................................................................................. G-125.1 Read Registers Example ...................................................................... G-125.2 Write Registers Example ...................................................................... G-12


vi

List of Figures

2. INSTALLATION

2.1.1 Environmental Guidelines for Installation ................................................................ 2-1

2.5.4a 4 Wire Wye: 3 Element Direct Connection (For 120/208 to 347/600 Volt Systems) . 2-5

2.5.4b 4 Wire Wye: 3 Element Connection Using 3 PT's .................................................... 2-6

2.5.4c 4 Wire Wye: 2½ Element Connection Using 2 PT's ................................................. 2-7

2.5.4d 3 Wire Wye: 3 Element Direct Connection (For 120/208 to 347/600 Volt Systems) . 2-8

2.5.5a 3 Wire Delta: 2½ Element Using 2 PT’s and 3 CT’s ................................................ 2-9

2.5.5b 3 Wire Delta: 2 Element Using 2 PT’s and 2 CT’s ................................................. 2-10

2.5.6 3 Wire Single Phase: 2 Element Direct Connection ............................................... 2-11

2.6.1 RS-485 Intermediate Terminal Strip Connections .................................................. 2-13

2.6.2 RS-485 Communications Connections .................................................................. 2-14

2.6.3 RS-485 Topologies to Avoid .................................................................................. 2-15

2.7.1 kWh Pulse Output Connections ............................................................................. 2-16

3. OPERATION

3.3.1 3300 ACM Front Panel Displays ............................................................................. 3-2

3.3.2 3300 ACM Display Module Front Panel Features .................................................... 3-3

3.4.3 Programming Mode Display and Button Functions .................................................. 3-5

3.4.5 Field Programming Example ................................................................................... 3-7

3.4.6a Programmable Operating Parameters I .................................................................... 3-8

3.4.6b Programmable Operating Parameters II ................................................................... 3-9

4. MEASURED PARAMETERS

4.1.1a List of Measured Parameters .................................................................................. 4-2

4.1.1b List of Measured Parameters .................................................................................. 4-2

4.3.1 Thermal Demand Calculation ................................................................................... 4-5

4.3.4 Power Reading Polarities ......................................................................................... 4-8

5 COMMUNICATIONS

5.2.1 Remote Communication Methods ............................................................................ 5-1

5.8.1 Modbus Communications Connections .................................................................... 5-5

5.9.1 PLC/AB Communications Connections ................................................................... 5-7


vii

List of Figures

A MECHANICAL & MOUNTING DIMENSIONS

A-1 Display Module Front View ..................................................................................... A-1

A-2 Display Module Rear View ...................................................................................... A-1

A-3 Base Module Dimensions ....................................................................................... A-2

A-4 Terminal Block Dimensions .................................................................................... A-2

G SERIAL COMMUNICATIONS PROTOCOL

G-1 Read Registers Packet ........................................................................................... G-5

G-2 Write Registers Packet ........................................................................................... G-7

G-3a 3300 ACM Data Registers - Part I .......................................................................... G-8

G-3b 3300 ACM Data Registers - Part II ......................................................................... G-9

G-3c 3300 ACM Data Registers - Part III ...................................................................... G-10

G-3d 3300 ACM Setup Registers - Part IV .................................................................... G-11

G-4 Read Registers Example ...................................................................................... G-12

G-5 Write Registers Example ...................................................................................... G-12


viii


Introduction 1-1* Do not hipot test the phase current inputs.

BASE MODULE

DISPLAY MODULE

1. INTRODUCTION

1.1 DESCRIPTION

The 3300 ACM is a 16-bit, microprocessor based 3-phasepower meter which provides advanced features at anaffordable price. The 3300 ACM offers a cost-effectivealternative to analog metering and full-featured digitalinstrumentation packages, while still providing highaccuracy, high reliability, and high transient, surge andhipot withstand capabilities.

The basic model 3300 ACM can directly replace up to fourtraditional analog meters and selector switches, whileadditional measurement options make it possible toreplace even more. Further savings are realized through aunique 2-module design, which simplifies wiring andreduces installation time. This makes the 3300 ACMperfectly suited for economical metering on 3-phaseindustrial and commercial switchboards and switchgear.

An RS-485 communications port is standard, allowing the3300 ACM to be used as either a stand-alone powermonitoring station, or as one element in a large energymanagement network. The 3300 ACM is also availablewithout the display module, making it an ideal digitalpower transducer for PLC, EMS, DCS and SCADA appli-cations. Alternatively, the communications port can beused to pulse kW hours.

A choice of many measurement functions and displaysThe 3300 ACM may be configured to operate in Wye(Star), Delta, or Single Phase voltage modes. The basicmodel provides the following measurements:

• 3-phase line-to-neutral voltages

• Line-to-neutral average voltage

• 3-phase line-to-line voltages

• Line-to-line average voltage

• Current on each phase

• Average current

• kW, total for all phases

• kWh, total for all phases

Voltage and current measurements are true RMS, includ-ing harmonics. Many other measurements are offered asoptions, including kVAR, kVARh, kVA, kVAh, powerfactor, and frequency. Demand and minima/maximavalues on all measured parameters are also available. SeeChapter 4 for a complete listing of basic and optionalmeasurements.

The high-visibility 20-character LCD display of the display/keypad module provides many convenient options forpresenting measured data, including simultaneous displayof: Volts, Amps, and Power Function; all 3 voltage phases;or all 3 current phases.


1-2 Introduction

Quick and easy installationThe separate display and base modules of the 3300 ACMsimplify wiring connections and reduce installation time.The compact, rugged base module provides a large, utilityapproved, barrier-style terminal strip for reliable connec-tions. No transducers are required. Connections fromCTs can be made directly (via shorting blocks). No PTsare required for 4-wire Wye or Single Phase systemsunder 347 VAC line-to-neutral or 600 VAC line-to-line.PTs are required on all Delta systems.

The separate display module is panel mountable, requir-ing only a single cutout. The module has been designed tofit ANSI C39.1 cutouts, simplifying replacement of exist-ing analog meters. The display module connects via asingle pluggable cable to the base module, allowing thebase module to be mounted inside the switchgear cabinet.No switches or additional wiring are required on thepanel door.

Field programmabilityVolts and Amps Scales, Volts Mode (wye, delta, singlephase), and Baud Rate are all easily programmable fromthe front panel. A portable or remotely located computercan also be used to program setup data via the communi-cations port. All setup data is saved when 3300 ACMpower is turned off. All programming is passwordprotected.

Communications and SCADA compatibilityThe 3300 ACM is equipped with an optically isolated RS-485 communications port for remote display of measureddata. This allows the 3300 ACM to be incorporated as oneelement within sophisticated SCADA or Energy Manage-ment Systems.

RS-485 can operate as a 2-wire LAN with up to 32 devicesper loop, and is capable of addressable polling of multipleunits, packet transmission, and high throughput (300 to19,200 baud).

The 3300 ACM maintains communication compatibilitywith Power Measurement’s other 3000 series devices andlow cost PC-based power monitoring systems: M-SCADA,L-SCADA, and PowerView. These systems can be used todisplay the real-time measured data from each 3300 ACM,or for the entire power distribution system.

The basic model 3300 ACM also provides ModiconModbus compatiblity. Basic Power Measurement commu-nications uses an open protocol that can provide access byother third-party systems. A comprehensive descriptionof the 3300 ACM communications protocol can be found inAppendix G.

New feature upgrades made easyThe 3300 ACM has been designed to maintain its positionat the forefront of current technology through upwardcompatibility. An advanced system architecture wasdeveloped by Power Measurement to support simpleupgrading of the 3300 ACM on-board operating firmware.New features or performance enhancements can beinstalled easily via the device's communications port -without any interruption to electrical service.

Each 3300 ACM should be connected to a local RS-485communications bus during initial installation to allowfirmware upgrades to be accomplished without the needfor wiring disconnections or removal of units from theirmountings. This is described in detail in Chapter 2.

kWh pulsing featureThe 3300 ACM offers an additional feature which allowsthe RS-485 port to be used as a kWh pulse output, suitablefor driving an external relay. This is also described indetail in Chapter 2.

1.2 SYSTEM APPLICATIONS

The 3300 ACM is a state-of-the-art alternative to tradi-tional analog electro-mechanical metering devices. Be-cause of its unique measurement, display, and communi-cations capabilities the 3300 ACM should be consideredfor use in:

a) Utility installations and substation metering.

b) Co-generation systems.

c) Office and commercial buildings, including largestores, shopping centres, and hotels.

d) Hospitals.

e) Telephone exchanges.

f) Factories and other industrial sites, including pulpand saw mills, chemical processing plants, breweries,and other processing or manufacturing facilities.

g) Multi-user sites where allocation of electrical costs isdesirable.

h) Any other installation which uses significant amountsof electrical energy or where remote monitoring isneeded.


Installation 2-1

2. INSTALLATION Enclosure ConsiderationsThe enclosure that the 3300 ACM is mounted in (typically aswitchgear cabinet) should protect the device from atmo-spheric contaminants such as oil, moisture, dust, andcorrosive vapours, or other harmful airborne substances.

The mounting enclosure should be positioned such that thedoors may be opened fully for easy access to the wiring to the3300 ACM display module, base module, and all relatedcomponents to allow for convenient troubleshooting. Whenchoosing the enclosure size, allow for extra space for allwiring, intermediate terminal strips, shorting blocks, or anyother required components.

3300 ACM MOUNTINGAppendix A provides the mounting dimensions for thedisplay and base modules of the 3300 ACM.

The display module of the 3300 ACM can be panel mountedfor easy access and viewing. This module is typicallymounted on the switchgear cabinet door. The panel intowhich the display module is to be mounted requires four holesand one cutout to allow for connection of the display cable. Thelayout of the display module mounting studs and cableconnector have been designed such that the module will fit anexisting ANSI C39.1 panel cutout.

ENVIRONMENTAL CONDITION ACCEPTABLE RANGE

Operating Temperature 0oC (32oF) to 50oC (122oF)

Storage Temperature -30oC (-22oF) to +70oC (158oF)

Relative Humidity 5 to 95% non-condensing

Figure 2.1.1 Environmental Guidelines for Installation

DANGER

During normal operation of thisdevice, hazardous voltages arepresent which can cause severe injuryor death. These voltages are presenton the terminal strips of the deviceand throughout the connectedpotential transformer (PT), currenttransformer (CT), and control powercircuits. Installation and servicingshould be performed only by quali-fied, properly trained personnel.

CAUTION

The 3300 ACM offers a range of hardwareoptions that affect phase voltage, phasecurrent, and power supply input ratings.The label of the 3300 ACM base modulelists all equipped options. Appendices Cand D define all options and their associ-ated ratings. This chapter provides de-tailed installation instructions applicable toeach hardware option.

2.1 LOCATION & MOUNTING

Environmental ConditionsThe primary concern in installing the 3300 ACM should bethe environment. The 3300 ACM should be mounted in adry, dirt free location away from heat sources and very highelectric fields. To operate properly and effectively, environ-mental conditions for both the 3300 ACM display and basemodules should fall within the guidelines listed in Figure2.1.1.

The 3300 ACM base module should be separated from otherequipment and plant walls to allow for convection cooling,which draws a vertical column of air upward over the device.This cooling air must not exceed +70oC (158oF) at any pointimmediately below the base module.


2-2 Installation

NOTE

It is very important that communicationswiring be made to the RS-485 port of ev-ery 3300 ACM being installed. See section2.6 for detailed instructions on communi-cations connections.

2.3 POWER SUPPLYCONNECTIONS

Power Supply OptionsThe basic model 3300 ACM can be powered by 108 to 132VAC/47 to 66 Hz at 0.25 Amps. A number of power supplyoptions are also available. The label on the base moduleindicates if the unit is equipped with one or more of theseoptions.

P240 OPTIONThis option can be powered by 216 to 264 VAC/47 to 66 Hzat 0.125 Amps.

P24 OPTIONThis option can be powered by 22 to 27 VDC at 0.3 Amps.

P120DC OPTIONThis option can be powered by 85 to 132 VAC at 47 to 440Hz or 110 to 170 VDC, both at 0.1 Amps.

P240DC OPTIONThis option can be powered by 85 to 264 VAC at 47 to 440Hz or 110 to 340 VDC, both at 0.1 Amps. Note that unitsequipped with this option are supplied with an overheightbase module enclosure (see Appendix A for dimensions).

Power Sources and ConnectionsThe basic model or P240 option can be powered from adedicated fused feed, or from the voltage source which it ismonitoring, as long as it is within the supply range. TheP24 option must be powered from a dedicated fused feed. Ifan AC power supply is being used, connect the line supplywire to the 3300 ACM L/+ terminal and the neutral supplywire to the N/- terminal. If a DC power supply is beingused, connect the positive supply wire to the 3300 ACM L/+terminal and the negative (ground) supply wire to the N/-terminal.

NOTE

The 3300 ACM -TRAN model does notprovide a display module. All data mustbe accessed via the communications portof the base module. Refer to Appendix G.

The base module of the 3300 ACM can be mounted flushagainst any flat surface. The unit provides four slots on itsmounting flange for this purpose. The base module istypically mounted inside the switchgear cabinet. Labellingon the base module has been positioned to allow the moduleto be mounted against a wall with the terminal strip in avertical orientation. However, the module can be mountedin whichever orientation is most convenient.

WARNING

The base module can be mounted on thedoor of the switchgear cabinet; however,some electrical codes may prohibit ex-tending voltages greater than 120 VACline-to-neutral or 208 VAC line-to-line tothe door. If this is the case, mount thebase module inside the cabinet as de-scribed above, or use the 3300 ACM withPTs that provide 120 VAC secondaries(see Section 2.5).

Note that the distance between the mounting locations ofthe display and base modules will be limited by the length ofthe interconnecting display cable (6 feet / 1.82 meters).

2.2 GENERAL WIRINGCONSIDERATIONS

Connections to the 3300 ACM are made to the terminal striplocated on the base module. Appendix A provides terminalblock dimensions. 12 AWG (4mm2) to 14 AWG (2.7mm2)gauge wire is recommended for all electrical connections.Ring or spade terminals may be used to simplify connection.

CAUTION

All wiring must conform to all applicablelocal electrical codes.


Installation 2-3

2.4 CHASSIS GROUNDCONNECTION

The ground terminal, G, of the 3300 ACM serves as the zerovoltage reference point for voltage measurements, as well asthe chassis ground connection for the meter. This terminalmust be connected to earth ground.

A good, low impedance chassis ground connection isessential for accurate measuements and proper protection.It should be made to the switchgear earth ground using adedicated 14 AWG (2.7mm2 ) gauge (or larger) wire to apoint where there will be no voltage error due to distributionvoltage drops. Do not rely on metal door hinges as aground path. Ensure that the screw has been tighteneddown securely onto the ground wire.

CAUTION

The G terminal of the 3300 ACM must beconnected properly in order for the noiseand surge protection circuitry to functioncorrectly. Failure to do so will void thewarranty.

2.5 PHASE VOLTAGE AND PHASECURRENT INPUT CONNECTIONS

2.5.1 PHASE VOLTAGE INPUTS

V1 Input ConnectionThe 3300 ACM uses the V1 input as the reference formaintaining phase relationships for all power and energyrelated measurements. For any system configuration, the V1input must be connected to ensure accurate readings andthe correct operation of the 3300 ACM.

Direct ConnectionWhether or not potential transformers (PTs) are requireddepends on the nature of the system being monitored, thevoltage levels to be monitored, and the input option of the3300 ACM.

BASIC MODELThe basic model can be used for direct connection to Wyesystems up to 347 VAC line-to-neutral/600 VAC line-to-line or Single Phase systems up to 347/694 VAC. Thesecan also include 120/208 VAC Wye, 120/240 VAC SinglePhase, 277/480 VAC Wye, and 277/554 VAC Single Phasesystems.

HIACC OPTIONSThe HIACC options provide higher measurement accuraciesthan the basic model. A guaranteed 0.25% accuracy isprovided on phase voltage and phase current measure-

ments, rather than the 0.5% accuracy of the basic model (seeAppendix C for complete specifications).

Devices equipped with any one of the HIACC options aredesigned to be used with the specific system voltage definedby the option. For example, a 3300 ACM - HIACC: 120should be used with a 120/208 VAC Wye or 120/240 VACSingle Phase system. Other HIACC options includeHIACC:277 and HIACC:347.

If a device equipped with a HIACC option is used at anyvoltage lower than what it is rated for, the accuracy of thevoltage measurements must be derated accordingly. Pleaseconsult your local Power Measurement sales representativeor contact Power Measurement directly for more informa-tion.

Using Potential TransformersIf Wye system voltages are over 347/600 VAC, Single Phasesystem voltages are over 347/694 VAC, or the system is aDelta configuration, PTs are required.

CAUTION

PTs are always required for Deltasystems.

PTs are used to scale down the line-to-neutral voltage of aWye or Single Phase system, or the line-to-line voltage of aDelta system to within the rated input scale of the 3300ACM. The basic 3300 ACM can be used with PTs that havesecondaries rated at 347 VAC or less. This can include 100/√3, 110/√3, 100, 110, 120, or 220 VAC secondaries.

Devices equipped with any one of the HIACC options aredesigned to be used with PTs with secondary ratings equalto the specific system voltage defined by the option (e.g. 120,277, or 347). Using PTs with other secondary ratings notequal to the option rating requires that the voltage accuracybe derated accordingly (see HIACC Options section above).

For proper monitoring, correct selection of PTs is critical. ForWye systems, the PT primary rating should equal the systemline-to-neutral voltage or nearest higher standard size. ForDelta systems, the PT primary rating should equal thesystem line-to-line voltage. For all system configurations,the PT secondary rating must be within the rated full scalerange of the 3300 ACM voltage inputs.

PT quality directly affects system accuracy. The PTs mustprovide good linearity and maintain the proper phaserelationship between voltage and current in order for thevoltage, kW, and power factor readings to be valid. Instru-ment accuracy Class 1 or better is recommended.


2-4 Installation

2.5.2 PHASE CURRENT INPUTS

The 3300 ACM uses CTs to sense the current in each phaseof the power feed. The selection of the CTs is importantbecause it directly affects accuracy.

Current Input OptionsThe 3300 ACM offers a choice of phase current inputoptions to match the type of CTs being used. The basicmodel 3300 ACM is compatible with CTs with 5 Amp fullscale secondaries. The 1AMP option provides compatibilitywith 1 Amp CT secondaries.

CAUTION

Refer to the label on the base module ofthe 3300 ACM to determine the equippedcurrent input option(s). Applying currentlevels incompatible with the current inputconfiguration will permanently damagethe device.

CT RatingsThe CT secondary should have a burden capacity greaterthan 3 VA.

The CT primary rating is normally selected to be equal to thecurrent rating of the power feed protection device. However,if the peak anticipated load is much less than the ratedsystem capacity then improved accuracy and resolution canbe obtained by selecting a lower rated CT. In this case theCT size should be the maximum expected peak current+25%, rounded up to the nearest standard CT size.

Other factors may affect CT accuracy. The length of the CTcabling should be minimized because long cabling willcontribute to inaccuracy. Also, the CT burden rating mustexceed the combined burden of the 3300 ACM plus cablingplus any other connected devices (burden is the amount ofload being fed by the CT, measured in Volt-Amps). The3300 ACM burden rating is given in Appendix C.

Overall accuracy is dependent on the combined accuracies ofthe 3300 ACM, the CTs, and the PTs (if used). Instrumentaccuracy Class 1 or better is recommended.

2.5.3 PT & CT CONNECTION

Figures 2.5.4a to 2.5.6 illustrate all required phase voltageand phase current connections for various circuit configura-tions to ensure correct installation. Phasing and polarity ofthe AC current and voltage inputs and their relationship iscritical to the correct operation of the unit.

All phase voltage sense leads should be protected bybreakers or fuses at their source. In cases where PTs are

required, if the power rating of the PTs is over 25 Watts thesecondaries should be fused.

DANGER

PT secondary circuits are capable ofgenerating lethal voltages andcurrents with their primary circuitenergized. Standard safety precau-tions should be followed whileperforming any installation or serviceon the device (e.g. removing PT fuses,etc.)

CTs should be connected to the device via a shorting block ortest block to facilitate the safe connection and disconnectionof the CTs.

DANGER

CT secondary circuits are capable ofgenerating lethal voltages andcurrents when open circuited withtheir primary circuit energized.Standard safety precautions shouldbe followed while performing anyinstallation or service on the device(e.g. shorting CT secondaries, etc.)

Questions regarding proper working procedures should bereferred to qualified personnel.


Installation 2-5

MODEL: 3300 ACM

SERIAL NUMBER:

OPTIONS:

ELECTRICAL RATINGS

POWERMEASUREMENTLTD.

6703 RAJPUR PLACE

VICTORIA, B.C.

CANADA V8X 3X1

MADE IN

CANADA

+-I32

I31

I22

I21

I12

I11V3

V2

V1

L

NG

CT SHORTING SWITCHOR TEST BLOCK

LINE

LOAD

EXPORT/REVERSE/NEGATIVE

IMPORT/FORWARD/POSITIVE

2A

2A

2A

Base ModuleCTs

A B C N

SWITCHGEARCHASSIS GROUND

NOTES: 1. VOLTS MODE = 4 WIRE WYE 2. Note the polarity of each CT.

Figure 2.5.4a 4 Wire WYE: 3 Element Direct Connection(for 120/208 to 347/600 Volt Systems)

! IMPORTANT !

It is important that all 3300 ACMinstallations include communica-tions wiring. Refer to Section 2.6for more information.

FUSES


SUPPLY POWER(dependent on equipped

power supply option - seeSection 2.3)

{

250 mA SLO BLO

2.5.4 CONNECTION FORTHREE PHASE WYE(STAR) SYSTEMS

Figures 2.5.4a to 2.5.4d provide wiring diagrams for 4 and 3wire Wye system configurations.

For a 4 wire Wye system, the 3300 ACM senses the line-to-neutral (or ground) voltage of each phase and current ofeach phase, making for an equivalent 3 element meteringconfiguration.

If the power system to be monitored is equal to or less than347/600 VAC, the 3300 ACM can be used for direct sensingof each phase, without the need for PTs.

The wiring diagram for these voltage ranges is shown inFigure 2.5.4a below. VOLTS MODE should be set to 4 WIREWYE.


2-6 Installation

MODEL: 3300 ACM

SERIAL NUMBER:

OPTIONS:

ELECTRICAL RATINGS


6703 RAJPUR PLACE

VICTORIA, B.C.

CANADA V8X 3X1

MADE IN

CANADA

+-I32

I31

I22

I21

I12

I11V3

V2

V1

L

NG

NOTES: 1. VOLTS MODE = 4 WIRE WYE 2. Note the polarity of each CT and PT.

Figure 2.5.4b 4 Wire WYE: 3 Element Connection Using 3 PTs

A B C N


LINE

CTs



2A

2A

2A

Base Module

LOAD

SWITCHGEAR CHASSISGROUND





{

250 mA SLO BLO

FUSES PT's FUSES

! IMPORTANT !It is important that all 3300 ACMinstallations include communica-tions wiring. Refer to Section 2.6for more information.

For Wye system voltages over 347/600 Volts, PTs must beused. When PTs are used, both the PT primary and second-ary must be wired in a Wye (Star). Voltage sense leadsshould be protected by breakers or fuses at their source. Ifthe power rating of the PTs is over 25 Watts the secondariesshould be fused.

This configuration is shown in Figure 2.5.4b below. Wiringmust be exactly as shown for correct operation. VOLTSMODE should be set to 4 WIRE WYE.


Installation 2-7

MODEL: 3300 ACM

SERIAL NUMBER:

OPTIONS:

ELECTRICAL RATINGS


6703 RAJPUR PLACE

VICTORIA, B.C.

CANADA V8X 3X1

MADE IN

CANADA

+-I32

I31

I22

I21

I12

I11V3

V2

V1

L

NG

NOTES: 1. VOLTS MODE = 3 WIRE WYE 2. Note the polarity of each CT and PT.

A B C N

FUSES PT's FUSES



LINE

CTs


IMPORT/FORWARD/POSITIVELOAD

2A

Base Module

2A





{

250 mA SLO BLO


The 3300 ACM also supports a 2½-element connectionscheme which requires only two PTs. In this mode, thephase B voltage reading is derived from the other availablevoltages.

This configuration is shown in Figure 2.5.4c. VOLTS MODEshould be set to 3 WIRE WYE.

WARNING

VOLTS MODE = 3 WIRE WYE will onlyprovide accurate power measurement ifthe voltages are balanced. If the phase Bvoltage is not equal to the phase A and Cvoltages, the power readings may notmeet the 3300 ACM accuracy specifica-tions.

Figure 2.5.4c 4 Wire WYE: 2½ Element Connection Using 2 PTs


2-8 Installation

Figure 2.5.4d 3 Wire WYE: 3 Element Direct Connection(For 120/208 to 347/600 Volt Systems)

MODEL: 3300 ACM

SERIAL NUMBER:

OPTIONS:

ELECTRICAL RATINGS


6703 RAJPUR PLACE

VICTORIA, B.C.

CANADA V8X 3X1

MADE IN

CANADA

+-I32

I31

I22

I21

I12

I11V3

V2

V1

L

NG

When the common or star point of a 3 wire Wye system isgrounded, the 3300 ACM may be connected directly withoutthe use of PT’s (provided the voltages are within the inputrange of the unit).

NOTES: 1. VOLTS MODE = 4 WIRE WYE. 2. Note the polarity of each CT. 3. The line transformer neutral must beequipotential with the SWITCHGEAR CHASSIS GROUND for this meter configuration to operate properly.

N

A B CCT SHORTING SWITCH

OR TEST BLOCK

2A

2A

2A


LOAD


LINE

Base Module




{

250 mA SLO BLO

CTs

FUSES



This configuration is shown in Figure 2.5.4d. The VOLTSMODE should be set to 4 WIRE WYE.


Installation 2-9

MODEL: 3300 ACM

SERIAL NUMBER:

OPTIONS:

ELECTRICAL RATINGS


6703 RAJPUR

VICTORIA, B.C

CANADA V8X

MADE IN

CANADA

+-I32

I31

I22

I21

I12

I11V3

V2

V1

L

NG

2A

2A

OPTIONAL PT POLARITY CONNECTION

VAB



2A

2A

VCB

LOAD



A B C


LINE

Base Module

Figure 2.5.5a 3 Wire DELTA: 2½ Element Using 2 PTs and 3 CTs

CTs




{

250 mA SLO BLO

FUSES PT's FUSES


2.5.5 CONNECTION FOR THREE PHASEDELTA SYSTEMS

For ungrounded (floating) 3 wire Delta systems, the 3300ACM always requires PTs and senses the line-to-linevoltages between each of the phases.

The 3300 ACM may be connected in either of two ways:using 2 or 3 CTs. Figure 2.5.5a below shows ungroundedDelta connection using 3 CTs. VOLTS MODE should be setto 3 WIRE DELTA.

NOTES: 1. VOLTS MODE = 3 WIRE DELTA 2. Note the polarity of each CT and PT.


2-10 Installation

MODEL: 3300 ACM

SERIAL NUMBER:

OPTIONS:

ELECTRICAL RATINGS


6703 RAJPUR PLACE

VICTORIA, B.C.

CANADA V8X 3X1

MADE IN

CANADA

+-I32

I31

I22

I21

I12

I11V3

V2

V1

L

NG

NOTES: 1. VOLTS MODE = 3 WIRE DELTA 2. Note the polarity of each CT and PT.



CTs

2A

VAB

VCB

2A

LOAD




2A

OPTIONAL PT POLARITY CONNECTION

2A

Figure 2.5.5b 3 Wire DELTA: 2 Element Using 2 PTs and 2 CTs




{

250 mA SLO BLO

Base Module

FUSES PT's FUSES


A B C

LINE

Figure 2.5.5b below shows ungrounded Delta connectionusing 2 CT’s. VOLTS MODE should be set to3 WIRE DELTA.


Installation 2-11

Figure 2.5.6 3 wire Single Phase: 2 Element Direct Connection

MODEL: 3300 ACM

SERIAL NUMBER:

OPTIONS:

ELECTRICAL RATINGS


6703 RAJPUR PLACE

VICTORIA, B.C.

CANADA V8X 3X1

MADE IN

CANADA

+-I32

I31

I22

I21

I12

I11V3

V2

V1

L

NG




2A

2A



A B N

CTs

LOAD

LINE



{

250 mA SLO BLO

FUSES

Base Module


2.5.6 CONNECTION FOR SINGLEPHASE SYSTEMS

Wiring for Single Phase systems is performed by connectingthe two voltage phases (each 180 degrees with respect toeach other) to the V1 and V2 inputs of the 3300 ACM, andthe outputs of the two corresponding current transformersto the I1 input pair and I2 input pair.

This is illustrated in Figure 2.5.6 below. Note that the V3input and I3 input pair are unused and should all begrounded. For Single Phase systems, the VOLTS MODE ofthe 3300 ACM should be set to SINGLE PHASE.

NOTES: 1. VOLTS MODE = SINGLE PHASE 2. Note the polarity of each CT.


2-12 Installation

2.6 COMMUNICATIONSCONNECTIONS

The 3300 ACM is equipped with an RS-485 communicationsport. Optical coupling provides full isolation between the RS-485 communication lines and the metering equipment.

Connections are made to the RS-485 terminals on the mainterminal strip.

NOTE

It is very important that communicationswiring be made to the RS-485 port of every3300 ACM being installed, even if remotecommunications are not initially required.All field service work including runningdiagnostics, testing, software upgrades,feature upgrades, etc., are performed viathe communications link.

The following sections describe wiring requirements forconnection with a master computer station or other device.Refer to Chapter 5 for information regarding communicationssetup parameters.

RS-485 ConnectionsRS-485 communications allows multiple devices to be con-nected on the same bus. Up to 32 devices can be connectedon a single RS-485 bus, which consists of a shielded twistedpair cable. The overall length of the RS-485 cable connectingall devices cannot exceed 4000 feet (1219 meters).

To connect an RS-485 communications bus to a computer orother RS-232C equipped device, an RS-232C to RS-485converter is required, such as Power Measurement’s COM32

or COM128. The COM32 offers a single RS-485 port, whilethe COM128 offers a total of four RS-485 ports that can eachsupport up to 32 devices.

General Bus Wiring ConsiderationsDevices connected on the bus, including the 3300 ACM,converter(s) and other instrumentation, must be wired asfollows:

a. Use a good quality shielded twisted pair cable for eachRS-485 bus. It is recommended that 22 AWG (0.4 mm2)or larger conductor size be used.

b. Ensure that the polarity is correct when connecting to theRS-485 port (+) and (-) terminals of each device.

c. The shield of each segment of the RS-485 cable must beconnected to ground at one end only.

CAUTION

Do not connect ground to the shield atboth ends of a segment. Doing so will al-low ground loop currents to flow in theshield, inducing noise in the communica-tions cable.

d. It is recommended that an intermediate terminal strip beused to connect each device to the bus. This will allowfor easy removal of a device for servicing if necessary.Figure 2.6.1 illustrates the correct connections to aterminal strip. Do not use the T-connection illustrated.The end of this section explains in more detail theconnection methods to avoid.

e. Cables should be isolated as much as possible fromsources of electrical noise.

SHLD SHLD

TerminalStrip

DISTANCE X

To nextdevice

To nextdevice

RS-485 Cable22 gauge shielded

twisted pair

SHLD

INCORRECT T-CONNECTIONCORRECT CONNECTION METHOD

DO NOTCONNECT

3300 ACM(or other RS-485 device)

Figure 2.6.1 RS-485 Intermediate Terminal Strip Connection

Installation 2-13


Calculating Overall Cable LengthWhen determining the overall length of an RS-485 communi-cation straight-line or loop connection, it is important toaccount for all cable segments. For example, when RS-485connections to the device are made via an intermediateterminal block (Figure 2.6.1), the lengths of cable between thedevice and the terminal block must be added to the total cabledistance. This length is equal to 2 times distance X in thediagram.

Connection Methods to AvoidAny device connection that causes a branch in the main RS-485 bus should be avoided. This includes star and tee (T)methods. Refer to Figure 2.6.3 for examples. These wiringmethods will cause signal reflections that may cause interfer-ence.

RULE OF THUMB

At any connection point on the RS-485bus, no more than two (2) cables should beconnected. This includes connectionpoints on instruments, converters, and ter-minal strips. Following this guideline en-sures that star and tee connections areavoided.

Recommended TopologiesDevices on an RS-485 bus are connected in a point-to-pointconfiguration, with the (+) and (-) terminals of each deviceconnected to the associated terminals on the next device. Thisis illustrated in Figures 2.6.2.

While there are many topologies that can be used to connectdevices on an RS-485 communication bus, the two recom-mended methods are the straight-line and loop topologies.

STRAIGHT-LINE TOPOLOGYThe straight-line wiring method is illustrated in Figure 2.6.2.The converter can exist at any position on the RS-485 bus,including an end point.

To reduce signal reflections that can corrupt data on the bus,each end point of the straight-line bus must be terminated.Termination resistors are connected between the (+) and (-)terminals of the device at each end of the bus. These resistorsshould have a rating of 1/4 Watt, and have a value whichmatches the line impedance of the cable being used. For 22AWG (0.4mm2) shielded twisted pair cable, values between150 and 300 ohms are typical. Consult the cablemanufacturer’s documentation for the exact impedance ofyour cable.

LOOP TOPOLOGYThe loop wiring method is illustrated in Figure 2.6.2 Theconverter can exist at any position on the RS-485 bus.

One advantage of the loop topology is that a single opencircuit fault condition anywhere on the loop will not result inthe loss of communication between the computer station andany of the remote devices.

The loop topology does not require termination resistors atany point on the bus.

3300 ACM

Installation and Operation M

anualPow

er Measurem

ent Ltd.

2-14Installation

Figure 2.6.2RS-485 Com

munications Connections

SHLD

RS-485 PORT RS-485 PORT


SHLD

3300 ACMBase Module

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

RS-485 CableAWG 22 shielded twisted pair. Overall length: 4000 ft. maximum.

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

SHLD+ _ SHLD+ _ SHLD+ _

SHLD + _SHLDSHLD + _+ _

3300 ACMBase Module

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

RS-485 CableAWG 22 shielded twisted pair. Overall length: 4000 ft. maximum.

SHLD

RT

SHLD

Termination Resistor

LastRS-485 Device

(End Point)

LastRS-485 Device

(End Point)

RTTermination Resistor

SHLD+ SHLD+

3300 ACMBase Module

RS-485 PORT

+

SHLD

3300 ACMBase Module

RS-485 PORT

SHLD + _ SHLD + _+ _

_ __

Computer orModem

PORT

RS-4

85

RS-232C to RS-485 Converter

RS-232C

PORT

RS-4

85


RS-232C

Computer orModem

LOOP TOPOLOGY

STRAIGHT-LINE TOPOLOGY

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

Installation2-15

3300 ACM

Installation and Operation M

anualPow

er Measurem

ent Ltd.

SHLD


RS-485 PORT

RS-485 PORT

PORT

RS-4

85

RS-232C

Computer orModem

RS-232C to RS-485 Converter SHLD

_+

3300 ACMBase Module

RS-485 PORT

_+

3300 ACMBase Module

RS-485 PORT

SHLD SHLD SHLD_+

_+

3300 ACMBase Module

RS-485 PORT

SHLD

DO NOTCONNECT


DO NOTCONNECT

3-way starconnectionpoint notallowed

PORT

RS-4

85

RS-232C

Computer orModem


+ _SHLD SHLD

_+ _+

_+

SHLD SHLD

SHLD _+_+SHLD

3300 ACMBase Module

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

3300 ACMBase Module

RS-485 PORT

STAR CONNECTION

T-CONNECTION

3300 ACMBase Module

RS-485 PORT

Figure 2.6.3RS-485 Topologies to Avoid


2-16 Installation

2.7 KWH PULSE OUTPUT

The RS-485 communications port of the 3300 ACM canalternatively be used to provide a kWh pulse output, suitablefor driving a relay. Figure 2.7.1 illustrates the connectionsrequired. Pulses can be configured as KYZ or set to user-selectable pulse width (10 to 990 ms). The maximum pulserate possible is 1 pulse per second. Section 3.8 describes theprogramming and operation of this function in more detail.

CAUTIONS

1. Use only a Power Measurement ap-proved external relay with the 3300ACM. Using a non-approved relaycan seriously damage the RS-485 portoutput and will void the 3300 ACMwarranty. Contact Power Measure-ment for complete information regard-ing relay specifications and applica-tions.

2. The RS-485 port of any 3300 ACMwhich is being used for kWh pulsingmust not be connected to any localRS-485 communications network.Doing so will inhibit all communica-tions on the network.

2.8 MAINTENANCE

The 3300 ACM contains a non-volatile memory (NVRAM)that provides an integrated battery backup system. Therated life of the NVRAM battery is seventy years at 50oC(122oF), 28 years at 60oC (140oF), and 11 years at 70oC(158oF).

If the unit operates at less than 50oC for 60% of the time,less than 60oC for 90% of the time, and less than 70oC for100% of the time, the expected life of the NVRAM battery is35 years. If the meter is operating in an environment wherethe temperatures regularly exceed 60oC, the NVRAM shouldbe replaced every ten years.

Contact Power Measurement or your local representative forinformation on NVRAM replacement.

NOTE

When the NVRAM is replaced, min/maxdata (if equipped) may be lost. It is rec-ommended that critical data be uploadedvia communications to a computer priorto servicing. Setup parameters and cali-bration of the unit will not be affected.

Other than NVRAM replacement, the 3300 ACM does notrequire any regular maintenance.

- +

ControlContacts

External RelayTo input of pulsecounter(e.g. PML's 3750PDC PowerDemandController)

+

-

Figure 2.7.1 kWh Pulse OutputConnections

Installation 2-17


2.9 FIELD SERVICECONSIDERATIONS

In the unlikely event that the 3300 ACM unit should fail,servicing will require disconnection and removal of the unitfrom its mounting for the purpose of repair, or for exchangewith a replacement unit. The initial installation should bedone in a way which makes this as convenient as possible:

1. All phase voltage sense leads should be protected bybreakers or fuses at their source such that the 3300ACM can be safely disconnected.

DANGER

PT secondary circuits are capable ofgenerating lethal voltages andcurrents with their primary circuitenergized. Standard safety precau-tions should be followed whileperforming any installation or serviceon the device (e.g. removing PT fuses,etc.)

2. A CT shorting block should be provided so that the3300 ACM current inputs can be safely disconnectedwithout open circuiting the CTs. The shorting blockshould be wired so that protective relaying is notaffected.

DANGER

CT secondary circuits are capable ofgenerating lethal voltages andcurrents when open circuited withtheir primary circuit energized.Standard safety precautions shouldbe followed while performing anyinstallation or service on the device(e.g. shorting CT secondaries, etc.)

3. All wiring should be routed to allow easy removal of theconnections to the 3300 ACM base module terminalstrips and the 3300 ACM itself.

Questions regarding proper working procedures should bereferred to qualified personnel.


2-18 Installation


General Operation 3-1

3. GENERAL OPERATION

3.1 INTRODUCTION

This chapter describes the following:

a) Power up procedure.

b) Front panel operation, included instructions fordisplaying real-time data and for performing fieldprogramming.

c) Basic device setup procedure.

d) Operation of the kWh pulse output feature.

For a complete and detailed list of all measured parametersprovided by the 3300 ACM, refer to Chapter 4.

Remote communications setup and operation are described inChapter 5.

NOTE

The model 3300 ACM-TRAN provides nodisplay/keypad module. Data is read, andfield programming performed, via thedevice’s communications port. Refer toChapter 5 for instructions regarding -TRAN operation. For the -TRAN model,disregard all references made to front paneloperations in Chapter 3.

3.2 POWER UP

After all installation wiring is complete and has been doublechecked, the unit may be powered up by applying theappropriate voltage to the POWER input terminals.

The 3300 ACM will first enter its display mode, presenting Volts-Phase-Amps-Power Function. The power function displayedon power-up will depend on the measurement options withwhich the 3300 ACM has been equipped.

NOTE

In circumstances where a power functionrequires many significant figures or charac-ters to be clearly interpreted, the powerfunction will not be displayed simulta-neously with the Volts-Phase-Amps dis-plays. In this case, the Power Functionfield of the display may initially appearblank on power up.

To display the power function, press theFUNCTION button. This will allow thepower function to be presented using theentire width of the display, replacing theVolts-Phase-Amps display. To return tothe Volts-Phase-Amps display, press thePHASE button.

The measured values initially appearing may not be correct,since the unit has not yet been told a number of necessarypieces of information about the installation. The process ofgiving the 3300 ACM this information is known as fieldprogramming.

The 3300 ACM display mode and field programming modeare each described in detail in the following sections.


3-2 General Operation

FULL WIDTH DISPLAYSVery large measured values (e.g. kW Hours) andparameters with large display labels (e.g. kW DMDMAX) are presented using the entire display (Figure3.3.1c).

NOTE

If a full width display is being shown, thePHASE button can be used to return tothe Volts-Phase-Amps display.

Display ResolutionThe 3300 ACM front panel can display readings with up to9 digits of resolution. The readings for most measuredparameters are displayed in integer format. Frequencyreadings are displayed with one decimal place of resolution.

Voltage, current, and power parameters can be displayedwith additional decimal resolution by using the DISPLAYDECIMALS parameter. This is discussed in Section 3.6

Auto-Ranging UnitsLarger measured values will automatically be displayedusing the letter K as the thousands delimiter (e.g. 16K8Volts). Some measured parameters also provide negativevalues, such as Reverse kW, or Reverse kVAR.

Figure 3.3.1 3300 ACM Front Panel Displays

a) Standard Phase Display

b) 3-Phase Display

c) Full Width Display

3.3 DISPLAY MODE

3.3.1 FRONT PANEL DISPLAY

Display TechnologyThe 3300 ACM provides a unique and very flexible userinterface. The display/keypad module supplied with thebasic model features a large, high-visibility, 20-characterLCD display.

Data Displays and FormatsThe display can present a wide variety of information inmany different formats. The following information andformats can be displayed:

BASIC PHASE DISPLAYThis display is presented on initial power-up (refer toFigure 3.3.1a). Voltage and current are displayed forthe selected phase (φ), along with a power function. ThePHASE button is used to advance through each phasein sequence, while a selection of power functions can beaccessed using the FUNCTION button. The format ofthe phase labels and numeric readings can be pro-grammed to conform to world conventions. This isdescribed in Section 3.6

3-PHASE DISPLAYSConcurrent display of readings for all three phases ofVOLTS or all three phases of AMPS is possible (Figure3.3.1b). The PHASE button is used to access thesedisplays. Power functions will not be shown since theentire display is used to present all three phases ofinformation.



AMPS4-digit

POWERFUNCTIONS

5-digit / 8-character

LCD DISPLAYHigh visibility 0.4’’ character

PHASEindicator

VOLTS4-digit

DISPLAY MODULEBUTTONS

Long life, sealed, stainlesssteel membrane switches

3.3.2 FRONT PANEL BUTTONS

The 3300 ACM uses two long-life, stainless steel membraneswitches for parameter selection and programming functions.(See figure 3.3.2)

Phase ButtonIf the standard display is being viewed, the PHASE buttonwill advance through each phase. The sequence of phasereadings depends on the device setup, including the VOLTSMODE selected. Device setup is described in Section 3.4 Thephase (φ) field of the front panel display indicates the phasefor which readings are being displayed. The following formatfor phase labels are used. Note that the examples use thedefault phase labels: A, B, C. These labels can be redefined asdescribed in Section 3.6.

Single-phase labels indicate line-to-neutral values arebeing displayed for the indicated phase.

Dual-phase labels indicate line-to-line values are beingdisplayed for the indicated phase.

These labels indicate that the average values for allphases are being displayed for either line-to-neutral orline-to-line configurations, respectively.

Figure 3.3.2 3300 ACM Display Module Front Panel Features



Function ButtonA preset list of useful power function parameters is availablevia the FUNCTION button. Pressing the FUNCTION buttonadvances through each measured parameter.

Two power function parameters are provided by the basicmodel 3300 ACM:

1) kW TotalThis parameter represents the total real power for all3 phases.

2) kWh TotalThis is the total real energy consumed for all 3phases, and is the net difference of power importedand power exported.

The 3300 ACM can also be equipped with additional mea-sured parameter options. All optional parameters areaccessible via the FUNCTION button, with the sequence ofparameters dependent on the total options installed.

A complete description of each parameter is provided in Chapter4.

AUTO FUNCTION CYCLING MODEThe 3300 ACM can be made to automatically cycle the frontpanel display through a preset sequence of measured param-eters:

• 3-phase Volts, line-to-neutral

• 3-phase Volts, line-to-line

• 3-phase Amps

• Frequency, kW Total

To start the cycling mode, hold down the PHASE button formore than 3 seconds, then release. The displays will be cycledat 4 second intervals. Pressing any button will return thedisplay to the regular non-cycling viewing mode.

NOTES

1. The Frequency parameter will be dis-played only if the 3300 ACM is soequipped.

2. The Frequency-kW display is only avail-able in the Auto Function Cycling modeand cannot be found in the regulardisplay modes.

The following phases of readings are available in each systemconfiguration (set by the VOLTS MODE parameter):

VOLTS MODE = 4 WIRE WYE, 3 WIRE WYE, DEMO.For each of these modes, the PHASE button will advancethrough:

• line-to-neutral average of the three phases

• line-to-neutral values for each phase

• line-to-line average of the three phases

• line-to-line values for each phase

• 3-phase line-to-neutral Volts display: V(LN)

• 3-phase line-to-line Volts display: V(LL)

• 3-phase Amps display

VOLTS MODE = 3 WIRE DELTAThe PHASE button will advance through:

• line-to-line values for each phase

• line-to-line average of the three phases

• 3-phase line-to-line Volts display: V(LL)

• 3-phase Amps display

VOLTS MODE = SINGLE PHASEThe PHASE button will advance through:

• line-to-neutral values for each phaseand the line-to-line value

• line-to-neutral average of the two phases



Press and hold down the PHASE andFUNCTION buttons together to enteror exit Programming Mode.

While in Programming Mode, pressand release the CURSOR andINCREMENT buttons quickly togetherto advance to the next setupparameter.

Display reads“POWER MEASUREMENT’’when Programming Mode has beenentered.

Increments the digit oradvances to next option

Moves cursor left by oneposition

Programming Modebutton functions

Figure 3.4.3 Programming Mode Display and Button Functions

3.4 FIELD PROGRAMMING

3.4.1 INTRODUCTION

Basic device programming can be performed quickly andeasily from the front panel, or via the communications portusing a portable or remotely located computer. Basic setupparameters include scaling factors for the voltage and currentinputs, voltage mode (wye, delta, etc.), and communicationssettings.

Power Measurement’s PC-based M-SCADA, L-SCADA andPowerView software fully supports 3300 ACM programming,providing a number of parameter screens which make setupquick and easy. The open communications protocol of the3300 ACM also allows free access to all programming param-eters using any compatible third-party system.

Setup and other critical information are saved when power isturned off. All programming is password protected.

A complete list of all programmable setup parameters isprovided in Section 3.4.6.

This manual describes procedures for programming the 3300ACM from its front panel only. For information on program-ming via communications refer to the manual for the softwareused. For third-party access, Appendix G provides informa-tion on the Power Measurement protocol used by the 3300ACM. For details on the Modbus protocol, contact PowerMeasurement or your local representative.

3.4.2 ENTERINGPROGRAMMING MODE

To program the setup parameters of the 3300 ACM from thefront panel, the user must first enter programming mode. Toenter programming mode, pressing and holding down theCURSOR and INCREMENT buttons together. Whenprogramming mode is first entered, ‘POWER MEASURE-MENT’ will be shown on the display.

The user can return to display mode at any time by againpressing and holding down the CURSOR and INCREMENTbuttons together

3.4.3 PROGRAMMINGBUTTON FUNCTIONS

In programming mode, the buttons of the front panel take onnew programming functions. The label below each buttonindicates its alternate function.

• CURSOR. Moves the cursor left one digit. The cur-sor position will wrap around to the right of thenumber if advanced past the left-most digit

• INCREMENT. Increments the digit under the cursor,advances through a number of preset values, or togglesa YES/NO option.

To advance to the next parameter in the list, press and quicklyrelease the CURSOR and INCREMENT buttons together.



3.4.4 ENTERING AND CHANGINGTHE PASSWORD

Pressing the CURSOR and INCREMENT button combinationonce will advance past the ‘POWER MEASUREMENT’display to the first parameter of the programming modewhich is the PASSWORD.

When the 3300 ACM is shipped, the PASSWORD will be 0.The correct PASSWORD must be entered if any parametervalues are to be changed. If the password is not entered,setup parameter values may still be viewed, but not modified.

To change the password, the present password must first beentered. To change the password the CURSOR and INCRE-MENT button combination should be pressed repeatedly toadvance past all parameters until the password parameter isdisplayed again. This time the new password should beentered. Once this has been done, returning to display modewill cause the password to be changed.

3.4.5 ACCESSING ANDMODIFYING PARAMETERS

Parameter ListThe CURSOR and INCREMENT button combination can bepressed to advance through each parameter.

The entire parameter list wraps around. If a parameter ismissed, the CURSOR and INCREMENT button combinationmay be pressed repeatedly to return to the desired parameter.

DIAGNOSTIC GROUPThe group of parameters listed under the heading DIAGNOS-TICS are not typically used in the normal operation of the3300 ACM. To make field programming as efficient aspossible, the diagnostics parameter group provides an accessparameter. The default setting for the DIAGNOSTIC MODE?access parameter is NO. If the value is not changed, pressingthe CURSOR and INCREMENT button combination will skipover that parameter group. If the value is set to YES, theCURSOR and INCREMENT button combination will advancethrough each parameter within that group.

Advancing past all parameters within the group will returnthe user to the Power Measurement display.

The diagnostic group of parameters is described in Section 3.9.

Defining New Parameter ValuesIf the correct password was entered, the user can modify anysetup parameter. As discussed in Section 3.4.3, the CURSORand INCREMENT buttons can be used to change individualdigits or select from a preset list of options for that parametervalue. Section 3.4.6 lists all programmable parameters andtheir range of possible values.

Attempting to set a parameter to a value outside of itsallowed range will cause that value to be ignored.

Parameter modifications are implemented immediately whenthe user advances to the next parameter.

Returning to Display ModeOnce all parameters have been set to their desired values,pressing and holding down the CURSOR and INCREMENTbutton combination together will return to display mode.



Figure 3.4.5 Field Programming Example

NOTE: Cursor position in the example is shown as an underscore line.In the actual display, cursor position is indicated by an underscored blinking character.

STEP ACTION: DISPLAY READS:

1. Press and hold down PHASE & FUNCTION buttons together to enter POWER MEASUREMENTprogramming mode.

2. Press and quickly release CURSOR & INCREMENT buttons once. PASSWORD= * * * *

3. Enter password by using INCREMENT and CURSOR buttons.Note: 3300 ACM is shipped with password = 0. PASSWORD= * * * 0

4. Press and quickly release CURSOR & INCREMENT buttons once. USING PTS?= NO

5. Press INCREMENT button once to toggle value to YES. USING PTS?= YES

6. Press and quickly release CURSOR & INCREMENT buttons once. PT PRIMARY= 1

7. Enter new value for PT PRIMARY. To set to 14400 (14.4 kV), firstset far right digit to 0 by pressing INCREMENT until display reads: PT PRIMARY= 0

8. Move cursor one digit left by pressing CURSOR button. PT PRIMARY= 0

9. Set digit required value by pressing INCREMENT. PT PRIMARY= 00

10. Repeat steps 8 & 9 above until all digits set. PT PRIMARY= 14400

11. Press and quickly release CURSOR & INCREMENT buttons once. PT SECONDARY= 1

12. Enter new value for PT SECONDARY. Follow steps 8 to 10 above,using INCREMENT and CURSOR buttons until display reads: PT SECONDARY= 120

13. Press and quickly release CURSOR & INCREMENT buttons to advanceto next parameter, or press and hold down to return to display mode. Volts, Phase, Amps, Power Function

Programming ExampleFigure 3.4.5 gives a step-by-step example of how to programoperating parameters from the front panel. The examplegiven shows how to set the PT PRIMARY and PT SECOND-ARY parameters for the device, then return to display mode.The example is given for a PT primary of 14.4 kV. Thesecondary is the required rating of 120 V.



Figure 3.4.6a Programmable Operating Parameters I

PARAMETER DESCRIPTION RANGE

3.4.6 OPERATING PARAMETERDESCRIPTIONS

Figures 3.4.6a and 3.4.6b provide a brief description of eachoperating parameter that may be programmed from the frontpanel or via communications.

More detailed descriptions of each operating parameter areprovided throughout this manual where operational featuresare described.

PASSWORD Must be entered correctly to allow changing the value of 4 digit numberany setup parameter(s) or to allow clear/reset of any function.

USING PTS? Selecting NO indicates the 3300 ACM voltage inputs are NO = direct connectionbeing connected directly to the power lines, without PTs. YES = input from PTsSelecting YES indicates PTs are being used.

PT PRIMARY Set to PT primary voltage rating. This parameter only 0 to 999,999 Voltsappears when USING PTS? parameter has been set to YES.

PT SECONDARY Set to PT secondary voltage rating. This parameter only 0 to 347 Voltsappears when USING PTS? parameter has been set to YES.

AMPS SCALE Sets full-scale AC input current for A, B, and C phases 0 to 32,000 Amps(CT primary current rating). See Section 3.5.

VOLTS MODE Sets Volts Mode for correct power system configuration. 4-WIRE WYEDemo mode provides preset values for all measurements 3-WIRE DELTAbased on input scales. Use for demonstration purposes only. SINGLE PHASE

DEMO3-WIRE WYE

UNIT ID Sets communications identification number for 3300 ACM. 1 to 9999Note: The number 0 may not be used for an ID as it isreserved for other purposes.

COM MODE Selects the function of the RS-485 port. RS485 = communicationsSee Sections 5.3. kWh PULSE = pulse output

kWh/PULSE Sets number of kW hours between pulses in kWh pulse mode. 0.1 to 9999.9 kWhParameter only appears when COM MODE = kWh PULSE.

PULSE FORMAT Sets the kWh PULSE output format. Parameter only appears kYZ, PULSEif COM PORT = kWh PULSE and kWh/PULSE is non-zero.

PULSE DURATION Sets the kWh PULSE pulse width in multiples of 10 milliseconds. 1 to 99Parameter only appears if PULSE FORMAT = PULSE.

BAUD RATE Baud Rate at which the 3300 ACM transmits and receives 300, 1200, 2400,information via communications. 4800, 9600, 19,200



PARAMETER DESCRIPTION RANGE

Figure 3.4.6b Programmable Operating Parameters II

PROTOCOL Selects the communications protocol. PML, MODBUS

REGISTER SIZE Selects Register Size for MODBUS communications. 16 BIT, 32 BITParameter only appears if PROTOCOL = MODBUS.

CLEAR ALL HOURS? Selecting YES will set the kW hours, kVAR hour, and NO, YESkVA hours readings to 0.

RESET MIN/MAX? Selecting YES will reset the Min/Max array. NO, YES

DEMAND PERIOD Sets length of the demand sub-period to be used in calculating 1 to 99 = minutes optional demand values. See Chapter 4.

# OF DMD PERIODS Sets number of sub-periods to be averaged in calculating the 1 to 15sliding window demand values. See Chapter 4.

FORMAT Sets the format of the phase labels and decimal delimiter. Phase: ABC, XYZ,CURSOR selects phase label or delimiter parameter. RYB, RST, 123INCREMENT selects options. Delimiter: period, comma

SHOW DECIMALS ? Allows high-resolution display of V, A, kW, kVAR, and kVA values NO, YES

CONTRAST/ANGLE Press INCREMENT to adjust contrast of the LCD display. -5 to 5Contrast changes

DIAGNOSTIC MODE? Setting this parameter to YES will allow access to the NO = bypass diagnosticsDIAGNOSTIC MODE parameter group listed below. YES = gain access

SERIAL NUMBER The user may view the 3300 ACM factory set serial number. 5 digit #

FIRMWARE VER These two parameters indicate the current version and revision Version = 4 digit #REV DATE date of the operating firmware (i.e. program) in the 3300 ACM. Date = dy/mo/yr

CHECKSUM Checksum value on program memory. Indicates PASS or FAIL. 6 characterhexadecimal #

STATUS FLAGS Indicates status of various internal systems. Should normally 6 characterread zero (0). hexadecimal #

CLEAR STATUS? Selecting YES will set all status flags (described above) to zero (0). NO, YES



3.5 SELECTING DIRECT OR PT INPUT &SETTING PT SCALES, AMPS SCALE,VOLTS MODE

This section details the minimum basic programming setuprequired for proper operation of the 3300 ACM.

Direct Connection or Using PTsThe setting of the phase voltage input parameters is depen-dent on the voltage of the system being monitored andwhether the 3300 ACM is being connected directly to thelines, or if PTs (potential transformers) are being used.

WARNING

PTs are required for connection to all Deltasystems.

DIRECT CONNECTIONThe basic model 3300 ACM supports direct connection toWye systems up to 347/600 VAC and Single Phase systemsup to 347/694 VAC without the need for PTs.

For direct connection, the USING PTS? parameter of the 3300ACM must be set to NO. The 3300 ACM will automaticallyselect the correct scaling.

PT CONNECTIONPTs must be used for Wye systems above 347/600 VAC,Single Phase systems above 347/694 VAC, and for all Deltasystems.

If PTs are used, set USING PTS? to YES. The following twoparameters which appear will then be PT PRIMARY and PTSECONDARY. These are used to tell the 3300 ACM what thePT voltage ratings are, allowing the 3300 ACM to set itsinternal full scale input references.

Set PT PRIMARY to the primary rating of the PTs used. Thisshould normally be equivalent to the full scale line levelswhich are being measured by the meter. For example, for a13.8 kV system, 120:1 ratio PTs with primary ratings of 14.4kV are typically used. For these PTs, set the PT PRIMARY to14400.

Set PT SECONDARY to the secondary rating of the PTs used.The maximum secondary voltage allowable is 347 VAC.

USING THE HIACC OPTIONThe HIACC (high accuracy) option of the 3300 ACM providesa preset input voltage scale of 120, 277 or 347 VAC. To ensureoptimum accuracy when using a 3300 ACM with this optioninstalled, direct connect only to systems with full scale levelsequivalent to the specified 3300 ACM input voltage. Forexample, a 277 VAC HIACC meter should only be used witha 277 VAC system.

If PTs are used with the HIACC option, always use PTswith secondary voltages equal to the specified 3300 ACMinput voltage, and set the PT SECONDARY parameter tothat value.

Amps ScaleThe basic model 3300 ACM provides 5 Amp phase currentinputs. If the CTs used are rated for a 5 Amp full scaleoutput, set the AMPS SCALE should be set to the primaryrating of the CTs being used.

The 3300 ACM also offers a 1AMP option which for use withCTs with 1 Amp full scale output.

If the CTs are not rated for a 5 Amp or 1 Amp full scaleoutput, contact Power Measurement or your local representa-tive for more information.

NOTE

For the above parameter settings,

PT PRIMARY x AMPS SCALE

should be less than 999,999,999 for correctdisplay of kW, kVAR, and kVA readingswhich have a maximum range of 999,999.

Volts ModeThe VOLTS MODE should be set according to the systemconnection configuration (4-WIRE WYE, 3-WIRE WYE, 3-WIRE DELTA, SINGLE PHASE). Refer to Chapter 2 for moreinformation.

The 3300 ACM also offers a demonstration mode which willgenerate dynamic readings for all real-time measurementsbased on the input scales programmed by the user. Thesereadings can be viewed from the front panel or via communi-cations. To use this feature, set VOLTS MODE to DEMO.



3.6 DISPLAY FORMAT

3.6.1 CHOOSING A DISPLAY FORMAT

The 3300 ACM front panel display can present numericinformation and phase labels in a number of different formatswhich reflect various world and industrial standards. TheFORMAT parameter is used for this purpose.

The front panel display can present measured values usingeither of the two following numeric formats:

a) 1234.5 This is the default. A decimal point is usedfor the decimal delimiter.

b) 1234,5 A comma is used for the decimal delimiter.

The decimal delimiter only affects Power Factor measurementsand voltage and current measurements in high-resolution modeif so equipped (see Section 3.6.2).

For the thousands delimiter (radix), the international stan-dard letter K is sometimes used (e.g. 12K5 represents 12500).Its use is dependent on the type of value being displayed.

The possible choices for the three letters used for the phaselabels are: ABC (default), XYZ, RYB, RST, and 123.

To set the FORMAT parameter, the CURSOR button is usedto select whether the numeric or phase label format is beingprogrammed. The INCREMENT button is then used toadvance through each format option.

3.6.2 HIGH-RESOLUTIONDISPLAY OPTION

NOTE

This feature is supported only by devicesequipped with firmware version 1.2.2.0 andlater.

The 3300 ACM can optionally display high-resolution valuesfor instantaneous voltage, current and power measurements.This option is selected by setting the DISPLAY DECIMALS

parameter to YES in programming mode.

In this mode, Volts and Amps will be shown to 1 decimalplace of resolution if the reading is below 100 (e.g. 87.5). Ifthe instantaneous kVA total is below 40 kVA, the readings forkW, kVA and kVAR are displayed as W, VA and VAR,respectively.

Minimum, maximum, demand, min/max demand, andenergy (hours) readings do not support this feature.

NOTE

1. It is important to realize that the 3300ACM’s accuracy is specified in per-centages of full scale reading. How-ever, the High-Resolution feature candisplay resolutions of readings greaterthan the actual accuracy of the meter.

As an example, if the current scale ofthe meter is set to 100, the specifiedaccuracy of current readings for a ba-sic model 3300 ACM would be

0.5% x 100 Amps = 0.5 Amps

With the high-resolution display op-tion enabled, the 3300 ACM can dis-play current readings with a resolutionof 0.1 Amps, which is greater that thespecified accuracy.

2. The 3300 ACM high-resolution featureis supported by the standard PowerMeasurement communications proto-col, but not by the Modbus communi-cations protocol.

3.7 ADJUSTING THE DISPLAYCONTRAST

The contrast of the LCD can be adjusted for optimumreadability at any given vertical viewing angle. PressingINCREMENT changes the contrast level of the display inpreset steps. Adjust until the best readability for a giveninstallation is achieved. A number corresponding to thepresent contrast level of the LCD display is shown.



3.8 USING THE KWH PULSEOUTPUT FUNCTION

The RS-485 port of the 3300 ACM can also be used to providea kWh pulse output which can be used to control an externalrelay. This, in turn, can connect to devices which use a kWhpulse counter input, such as Power Measurement's 3750 PDCpower demand controller.

To use the kWh pulse mode, COM MODE must be set tokWh PULSE.

CAUTION

If the 3300 ACM has been connected to anRS-485 network, setting the COM MODE to kWhPULSE will disable all communications on the net-work.

The kWh pulse output function can be programmed togenerate either a KYZ (state transition) or PULSE (squarewave) output. If the COM MODE has been set to kWhPULSE, kWh/PULSE appears as the next parameter. Thisparameter is used to set the number of kW hours betweenoutput pulses, and is settable within a range of 0.1 to 9999.9kWh.

If the kWh/PULSE is assigned a non-zero value, PULSEFORMAT appears as the next parameter, and allows the userto select between KYZ and PULSE.

If PULSE FORMAT = PULSE, the parameter PULSE DURA-TION appears next. This parameter allows the user to set thepulse width in multiples of 10 milliseconds. The valid range of thisparameter is 1 to 99 (10 to 990 milliseconds).

NOTE

1. The maximum pulse rate for the kWhpulse output function is 1 pulse persecond.

2. This feature is only valid for unitsequipped with firmware version1.1.0.0 or later.

Section 2.7 describes kWh pulse output connections and relayrequirements.

3.9 USING THE DIAGNOSTICPARAMETERS

As mentioned, the group of parameters accessed using theDIAGNOSTICS MODE? parameter are not typically used inthe normal operation of the 3300 ACM. These parameters do,however, have a number of special functions that can behelpful in some circumstances.

Serial Number, Checksum, & Status FlagsThese parameters are normally for Power Measurementinternal use. If you encounter any problem with the 3300ACM which you suspect is due to a device failure, write themdown and contact Power Measurement immediately. Youmay then be requested to view parameter values from thisgroup to help determine the source of the problem.

The CLEAR STATUS? parameter allows the status flags,accessed through the diagnostics mode, to be cleared.

Firmware Ver. and Rev. DateThe 3300 ACM has been designed to be totally upwardcompatible, ensuring that any new 3300 ACM featuresoffered by Power Measurement in the future can be easilyinstalled into an existing device in the field. This is per-formed using a simple firmware upgrade operation whichloads a new operating program into the device. The FIRM-WARE VER and REV DATE parameters indicate whichversion of firmware is currently installed in the 3300 ACM.This can be checked to determine if the 3300 ACM is operat-ing with the newest available firmware.


Measured Parameters 4-1

4. MEASURED PARAMETERS

4.1 INTRODUCTION

This chapter provides detailed descriptions of each measuredparameter provided by the basic model 3300 ACM , and thoseequipped as possible measurement options. These arecategorized as follows:

Measured Parameters:

a) Real-time

b) Energy

Measurement Modes:

a) Demand

b) Minima & Maxima

c) Bi-directional Energy

Figure 4.1.1 provides a complete listing of all measuredparameters, including their associated display labels. Thefigure indicates which measurements are included with thebasic model, and which are optional.

Appendix C lists measurement accuracies, display resolu-tions, and range of readings.

The following sections of this chapter provide additionalinformation on each parameter type.

Measured Parameter Display LabelsThe large number of measured parameter types and theirassociated measurement mode combinations requires that the3300 ACM display parameter names on its front panel usingspecial formats. Labels for each measurement, phase, andmode are listed in Figures 4.1.1a and 4.1.1b.

Items in parentheses are not included in the display labels.For example, kW Minimum for phase A would be:

KWa MIN

For the total for all phases, the word ‘total’ is omitted:

KW MIN

Phase labels are imbedded in the parameter labels to produce thedisplayed measurement name. For example, Voltage line-to-line, thermal demand, maximum for phase AB would be:

Vab DMD MAX

Reactive energy, total of all phases, exported would be:

KVRH EXP

As mentioned in Chapter 3, parameter names which require alarge number of characters will be presented using the entiredisplay.

Access to ParametersAll measurements provided by the basic model 3300 ACM,and all measurement options with which the 3300 ACM hasbeen equipped are continuously monitored or calculatedinternally by the 3300 ACM. As described in Chapter 3, theuser can access all parameters directly from the front panelusing the default PHASE and FUNCTION buttons.

All available measured parameters are always accessible viaremote communications (Chapter 5).


4-2 Measured Parameters

Figure 4.1.1a List of Measured Parameters I

DISPLAY LABELS DESCRIPTIONParameter Phase

NOTE: Items in parentheses are not included in the display labels. Phase labels are imbeddedinto parameter labels to produce the displayed measurement label. See Section 4.1 for examples.

Basic Measurements(Voltage) A, B, C, LN,

AB,

BC,

CA, L

L Voltage, per phase and average, line-to-neutral and line-to-line.

(Current) A, B, C, LN, AB, BC, CA, LL Current, per phase and average.

KW (total) Instantaneous real power flow (kW), total of all phases.

KWH TOT (total) Total accumulated real energy (i.e. kW hours) for all phases.

Optional MeasurementsV MIN a, b, c, LNav, ab, bc, ca, LLav Voltage minimums, per phase and average, line-to-neutral and line-to-line.

V MAX a, b, c, LNav, ab, bc, ca, LLav Voltage maximums, per phase and average.

V DMD a, b, c, LNav, ab, bc, ca, LLav Voltage thermal demand, per phase and average.

V DMD MIN a, b, c, LNav, ab, bc, ca, LLav Voltage thermal demand minimums, per phase and average.

V DMD MAX a, b, c, LNav, ab, bc, ca, LLav Voltage thermal demand maximums, per phase and average.

I MIN a, b, c, av Current minimums, each phase and average of all phases.

I MAX a, b, c, av Current maximums, each phase and average of all phases.

I DMD a, b, c, av Amps thermal demand, each phase and average of all phases.

I DMD MIN a, b, c, av Amps thermal demand minimums, per phase and average.

I DMD MAX a, b, c, av Amps thermal demand maximums, per phase and average.

I DMD* av Amps sliding window demand, average of all phases.

I DMD MIN* av Amps sliding window demand minimum, average of all phases.

I DMD MAX* av Amps sliding window demand maximum, average of all phases.

KW a, b, c Instantaneous real power flow (kW), per phase.

KW MIN a, b, c, (total) Instantaneous real power flow minimums, per phase and total.

KW MAX a, b, c, (total) Instantaneous real power flow maximums, per phase and total.

KW DMD a, b, c, (total) Instantaneous real power thermal demand, per phase and total.

KW DMD MIN a, b, c, (total) Instantaneous real power thermal demand minimums, per phase and total.

KW DMD MAX a, b, c, (total) Instantaneous real power thermal demand maximums, per phase and total.

KW DMD* (total) Instantaneous real power sliding window demand, total of all phases.

KW DMD MIN* (total) Instantaneous real power sliding window demand minimum, total of all phases.

KW DMD MAX* (total) Instantaneous real power sliding window demand maximum, total of all phases.

KWH IMP (total) Imported real energy (kWh), total of all phases.

KWH EXP (total) Exported real energy, total of all phases.



Figure 4.1.1b List of Measured Parameters II

DISPLAY LABELS DESCRIPTIONParameter Phase

Optional Measurements (continued)KVR a, b, c (total) Instantaneous reactive power flow (kVAR), per phase and total.

KVR MIN a, b, c, (total) Minimums for instantaneous reactive power flow, per phase and total.

KVR MAX a, b, c, (total) Maximums for instantaneous reactive power flow, per phase and total.

KVR DMD a, b, c, (total) Instantaneous reactive power thermal demand, per phase and total.

KVR DMD MIN a, b, c, (total) Instantaneous reactive power thermal demand minimums, per phase and total.

KVR DMD MAX a, b, c, (total) Instantaneous reactive power thermal demand maximums, per phase and total.

KVR DMD* (total) Instantaneous reactive power sliding window demand, total of all phases.

KVR DMD MIN* (total) Instantaneous reactive power sliding window demand minimum, total of all phases.

KVR DMD MAX* (total) Instantaneous reactive power sliding window demand maximum, total of all phases.

KVRH IMP (total) Imported reactive energy (kVARh), total of all phases.

KVRH EXP (total) Exported reactive energy, total of all phases.

KVRH TOT (total) Total reactive energy for all phases.

KVA a, b, c (total) Instantaneous apparent power flow (kVA), per phase and total.

KVA MIN a, b, c, (total) Minimums for instantaneous apparent power flow, per phase and total.

KVA MAX a, b, c, (total) Maximums for instantaneous apparent power flow, per phase and total.

KVA DMD a, b, c, (total) Instantaneous apparent power thermal demand, per phase and total.

KVA DMD MIN a, b, c, (total) Instantaneous apparent power thermal demand minimums, per phase and total.

KVA DMD MAX a, b, c, (total) Instantaneous apparent power thermal demand maximums, per phase and total.

KVA DMD* (total) Instantaneous apparent power sliding window demand, total of all phases.

KVA DMD MIN* (total) Instantaneous apparent power sliding window demand min., total of all phases.

KVA DMD MAX* (total) Instantaneous apparent power sliding window demand max., total of all phases.

KVAH TOT (total) Total apparent energy (kVAh) for all phases.

PF a, b, c, (total) Power factor (PF), per phase and total. Leading = PF LEAD, lagging = PF LAG.

PF MIN a, b, c, (total) Power factor minimums, per phase and total.

PF MAX a, b, c, (total) Power factor maximums, per phase and total.

PF DMD a, b, c, (total) Power factor thermal demand, per phase and total.

PF DMD MIN a, b, c, (total) Power factor thermal demand minimums, per phase and total.

PF DMD MAX a, b, c, (total) Power factor thermal demand maximums, per phase and total.

HZ (a) Frequency on phase A voltage

HZ MIN (a) Frequency minimum on phase A voltage

HZ MAX (a) Frequency maximum on phase A voltage

HZ DMD (a) Frequency thermal demand on Volts phase A.

HZ DMD MIN (a) Frequency thermal demand minimum on Volts phase A.

HZ DMD MAX (a) Frequency thermal demand maximum on Volts phase A.

VOLT HOURS (a) Accumulated time in hours when voltage on phase A is present (see Section 4.2.2).



4.2.2 ENERGY & VOLT-HOURS

IntroductionEnergy parameters include kW hours (kWH), kVAR hours(kVARH), and kVA hours (kVAH). All energy parameters aretrue RMS and represent the total for all 3 phases. kWH andkVARH each provide three separate measurement modeswhich indicate bi-directional power flow (see Section 4.3.3).

The Volt-Hour parameter can provide an indication of totalrunning time for an engine-generator set or other equipment.Volt-Hours will be accumulated during the time that thevoltage on phase A is maintained above:

a) 60 VAC for a basic model direct connected.

b) 60% of full scale for a basic model connected usingPTs, or for any HIACC option.

NOTE

The Volt-Hours parameter can only be usedto sense an active line-to-neutral voltage inWye or Single Phase systems.

Energy and Volt-Hours readings are updated once eachsecond. Maximum range of these readings is 999,999,999.Beyond this value, readings will roll over to zero (0).

Resetting the Energy CountersThe user can reset the value of all energy readings with whichthe 3300 ACM has been equipped (kWH, kVARH, kVAH).This can be performed using the CLEAR ALL HOURS?parameter from the front panel in programming mode, or viacommunications. Setting this parameter to YES will causethe import, export, and total counters for each parameter to becleared to zero (0) when the user exits programming mode.

4.2 PARAMETER DESCRIPTIONS

4.2.1 REAL TIME

Real-time parameters include all voltage, current, power,power factor, frequency and Volt-Hour measurements. Forphase dependent measurements, this includes per phasereadings, and averages or totals for all phases.

All real-time voltage, current and power measurements aretrue RMS and are updated each second.

For power measurements, a positive number (i.e. no sign)indicates real power in the forward direction (imported). Anegative number (i.e. negatively signed) indicates real powerin the reverse direction (exported).

Additional measurement modes available for real-timeparameters include demand and minima/maxima.

NOTE

Conventions used in regard to power factorlead/lag are discussed in Section 4.3.4.



Thermal Demand MeasurementsThe 3300 ACM provides a large number of optional thermaldemand measurements. Thermal demand values are calcu-lated for real-time measurements using a method which isequivalent to thermal averaging. For thermal averaging, thetraditional demand indicator responds to heating of a thermalelement in a Watt-Hour meter. The thermal demand period isdetermined by the thermal time constant of the element,typically 15 to 30 minutes. The demand period is the periodof time it would take the demand to ramp up to approxi-mately 63% of the steady-state value (see Figure 4.3.1).

For thermal demand, the programmable demand period isequal to the product of the following 2 parameters:

DEMAND PERIOD x # OF DMD PERIODS

This allows the user to match the power utility’s demandcalculation technique.

Each thermal demand measurement can optionally haveassociated minima/maxima parameters available.

NOTE

On the front panel display, thermal de-mand parameters are indicated using thelabel DMD. For example:

kW DMD = kW thermal demand

TIME

63%

100%

DEMAND

0%

DEMAND PERIOD

LOAD

PARAMETER &PARAMETER

DEMAND

Figure 4.3.1 Thermal Demand Calculation

4.3 MEASUREMENT MODES

Some optional measured parameters provide additionalmeasurement modes which are accessible from the front panelusing the FUNCTION button. The modes available to theuser are dependent on the parameter type, and the measure-ment options with which the 3300 ACM has been equipped.Figure 4.1.1 lists all modes applicable to each measuredparameter.

4.3.1 DEMAND

IntroductionPower utilities generally bill commercial customers based onboth their energy consumption (in kWH) and their peak usagelevels, called peak demand (in kW). Demand is a measure ofaverage power consumption over a fixed time period, typically30 minutes. Peak (or maximum) demand is the highestdemand level recorded over the billing period.

Demand measurement methods and intervals vary betweenpower utilities. Some common methods include: thermalaveraging, sliding window, and fixed interval techniques. The3300 ACM can perform demand calculations using both thethermal averaging and sliding window demand techniques.



Sliding Window Demand MeasurementsTo compute sliding window demand values, the 3300 ACMuses the sliding window averaging (or rolling interval) techniquewhich divides the demand interval into sub-periods. Thedemand is measured electronically based on the average loadlevel over the most recent set of sub-periods. This has theeffect of improving the response time as compared to the fixedinterval method.

Similar to thermal demand, the DEMAND PERIOD and# OF DMD PERIODS parameters allow the user to match thepower utility’s demand calculation technique. For slidingwindow measurements, DEMAND PERIOD represents thelength of the utility’s demand sub-period, while # OF DMDPERIODS represents the number of sub-periods which makeup the total demand interval. For example, with a 6 x 5minute (30 minutes total) sliding window method, demandwill be the average power consumption over the last six 5-minute periods. This allows the user to match virtually anytype of sliding window measurement method used by theutilities(e.g. 15x2, 6x5, 1x30).

Each sliding window demand measurement can optionallyhave associated minima/maxima parameters available.

NOTES

1. Using the sliding window method, the3300 ACM readings will always be ashigh or slightly higher than the utilityreadings.

2. On the front panel display, slidingwindow demand parameters are indi-cated using the label DMD followedby an asterisk. For example:

kW DMD* = kW sliding window demand

MANUAL DEMAND PERIOD SYNCHRONIZATIONThe internally-timed demand period for sliding windowdemand measurements can be synchronized to the powerutility’s demand period through performing a manualprocedure at the front panel of the 3300 ACM.

To reset the demand period, first change or toggle either theDEMAND PERIOD or the # OF DMD PERIODS setupparameter (without actually modifying it, but simply cyclingthe value from 5 back to 5, for example.). At the start of theutility’s demand period, quickly press and release both front-panel buttons simultaneously to advance to the next param-eter. The 3300 ACM demand period will be reset, and allsliding window demand measurements will be cleared.

Resetting the Demand ParametersBoth Thermal Demand and Sliding Window Demandparameters are reset whenever a change is made to the PTPRIMARY, PT SECONDARY, AMPSCALE, DEMANDPERIOD, or # OF DMD PERIODS either via communicationsor the front panel of the 3300 ACM.

In addition, all demand calculations can be reset from the frontpanel without changing any of the demand parameters. Toaccomplish this, access either DEMAND PERIOD or # OFDEMAND PERIODS in programming mode. Using theincrement button (right hand button) and cycle through thenumbers until the original value is reached again (e.g., ifdemand period is 15, then increment to 16, 17, 18, 19, 10,11.....15). The demand reset occurs as soon as the operator hasadvanced to the next parameter in programming mode.

Sliding Window Demand parameters are also reset whenevera RESET MIN/MAX is performed.

NOTES

1. MIN/MAX comparisons are not madeuntil five Thermal Demand periods ortwo Sliding Window Demand periodshave passed since the demand wasreset (i.e. not until the demand valueis within 99% of its' steady statevalue). This prevents either themaxima or the minima from alwaysreading zero (depending on the sign ofthe parameter) after a MIN/MAX re-set.

2. If a PT scale or CT scale has beenchanged, the minimum and maximumdemands are reset.

3. If the minima and maxima have beenreset within five Thermal Demand pe-riods or two Sliding Window Demandperiods of a demand reset, then theminimum and maximum demandswill read zero until the waiting periodfor either the thermal demand or thesliding window demand period is up.



4.3.3 BI-DIRECTIONAL ENERGY

Energy parameters provide three measurement modes whichindicate bi-directional power flow: imported, exported, and total.

Total measurements represent the difference between energyimported and exported for all three phases. This accumulatedvalue is incremented when power is being imported, anddecremented when reactive power is exported. Therefore, thisaccumulated value can be signed either positively (net import)or negatively (net export).

kWH and kVARH can provide all three modes. The kVAHenergy parameter provides only a total reading.

NOTE

Conventions used in regards to energy im-port/export are described in Section 4.3.4.

4.3.2 MINIMA / MAXIMA

IntroductionThe 3300 ACM can optionally provide minima and maximameasurements. These parameters record the extreme valuesfor real-time and demand parameters.

NOTE

On the front panel display, minima andmaxima are indicated using MIN andMAX, respectively.

Resetting Min / Max ParametersIf the 3300 ACM has been equipped with one or moreminima/maxima parameters, the user can reset their values.This can be perfomed using the RESET MIN/MAX? param-eter from the front panel in programming mode, or viacommunications. Setting this parameter to YES will cause allmin/max readings to be reset when the user exits program-ming mode.



- kVAREXPORT

θ = 45- kWEXPORT

+ kWIMPORT

θ = 90o to 180o θ = 0o to 90o

θ = 270o to 360oθ = 180o to 270o

PF = 100%

PF = 100%

PF LEAD(Power Factor

Leading)

PF LAG(Power Factor

Lagging)

PF LEAD(Power Factor

Leading)

PF LAG(Power Factor

Lagging)

PF = 0%

PF = 0%

Figure 4.3.4 Power Reading Polarities

+ kVARIMPORT

4.3.4 POWER READING POLARITIES

Figure 4.3.4 illustrates how the 3300 ACM interprets anddisplays signed values for power, energy import/exportindication, and power factor leading/lagging indication.

NOTE

The polarity of energy import/export read-ings can be reversed by reversing the polar-ity of the CTs connected to the 3300 ACM.

Communications 5-1


5. COMMUNICATIONS

5.1 INTRODUCTION

The 3300 ACM is equipped with an RS-485 communicationsport which allows the 3300 ACM to be integrated within largeenergy monitoring networks. The communications port isoptically isolated and transient protected, and can operate atbaud rates up to 19,200.

The 3300 ACM is fully compatible with Power Measurement’sPC-based M-SCADA or L-SCADA systems. M-SCADA / L-SCADA can display all measured parameters provided by the3300 ACM. M-SCADA / L-SCADA can also be used toremotely program all setup parameters. An open communica-tions protocol allows similar access by third-party systems,including the Modicon Modbus.

This chapter provides additional information regardingremote communications connections, programming, andgeneral operation.

Firmware Updating via the Comm. PortFuture 3300 ACM firmware updates, when made available byPower Measurement, can be quickly performed via the RS-485port; therefore, it is strongly recommended that all 3300 ACM devices beconnected onto a communication bus when installed, even if remotecommunications are not initially required. Updates are performed bydownloading of new firmware code from a locally connectedhost computer, or a remote computer connected via modem orother method.

5.2 RS-485 COMMUNICATION

RS-485 communication can be used to concurrently connectup to thirty-two remote devices on a single communicationsloop. Each device is given a unique UNIT I.D. (identificationnumber). In this way, each remote device may be monitoredand controlled from one location by a single computer/PLC.

The total distance limitation on a single RS-485 communica-tion network is 4000 feet (1219 meters) using 22 AWG(.4mm2) twisted pair shielded cable. Chapter 2 provideswiring diagrams for RS-485 network connection.

Communication methods between the remote RS-485 site andthe master computer station can include a direct RS-485connection (under 1219 meters), telephone lines with mo-dems, fiber-optic and/or radio links (see Figure 5.2.1). An RS-232C to RS-485 converter, such as Power Measurement’sCOM32 or COM128, is required between the RS-232C port ofthe computer or modem and the RS-485 network (see Chapter2).

RS-232 / RS-485CONVERTER

RS-485

RADIOLINK

FIBER OPTIC LINK,LEASED PHONE LINEor DEDICATED CABLE SITE 1

SITE 2SITE 3



LOCAL RS-485 LOOPSUPPORTS UPTO 32 DEVICES



TEL or FOTSMODEM

TEL or FOTSMODEM

RADIOTX / RX

MODEM

MODEMRADIOTX / RX

UP TO 4000 FT.

Figure 5.2.1 Remote Communication Methods


5-2 Communications

5.3 SETTING THE COM MODE, UNITI.D. & BAUD RATE

Before communication with the host computer/PLC ispossible, the user must first ensure that all other connecteddevices have been configured for RS-485 communication.

The next step is to program the communication parameters ofthe 3300 ACM, and all other connected devices. The follow-ing parameters must be programmed via the front panel ofthe 3300 ACM.

UNIT I.D.Each device on the RS-485 network must be given a uniqueidentification number. The range of possible values is 1 to9999.

COM MODETo communicate with the 3300 ACM, the COM MODE mustbe set to RS485.

NOTE

If the 3300 ACM has been connected to anRS-485 network, setting the COM MODE to kWhPULSE will disable all communications on the net-work. kWh PULSE mode is described below.

BAUD RATEThe baud rate of each device on the network must be set tocorrespond with the baud rate selected for the computer.Options include 300, 1200, 2400, 4800, 9600 or 19,200 baud.

CAUTION

When using a modem interface betweenthe host computer and any remotedevice(s), the user must ensure that thehost computer is not used to set the BAUDRATE parameter of any selected device out-side the working range of the modem. Do-ing so will cause that meter to cease com-municating. Re-establishment of commu-nication with that meter is then only pos-sible through performing the following twosteps:

a) Reset the baud rate of the remote de-vice from its front panel to a value withinthe working range of the modem.

b) Set the computer to communicate atthe baud rate the remote device hasbeen set to communicate at.

PROTOCOLSet the PROTOCOL parameter to PML to communicate withPower Measurement’s M-SCADA/L-SCADA software, or toMODBUS to communicate with the Modicon Modbus system.See Section 5.8 for more information on Modbus compatibil-ity.

Communications 5-3


5.4 3300 ACM -TRANMODEL OPERATION

The TRAN (transducer) model of the 3300 ACM provides allthe functions of the basic model 3300 ACM, except that it hasno front panel display or keypad. All measured parametersand programming parameters are accessed via communica-tions.

NOTE

All units ordered with the TRAN optionthat are to be used with Modbus communi-cations must also be ordered with theMOD option. For this option the factorypresets the device for Modbus communica-tions.

To initiate communications with the device, the factory-setUNIT I.D. and BAUD RATE must be used:

a) UNIT I.D. is set at the factory to be the last 4 digitsof the unit’s serial number, which can be found onthe rear cover of the unit. For example, a unit withserial number 71317 will be preset to UNIT I.D. of1317.

NOTE

If the unit has been ordered with the MODoption (Modbus communications), thenonly the last two digits of the units' serialnumber will be used as the unit's ID.(Modbus only allows unit ID's between 1and 247).

b) BAUD RATE is set at the factory to 9600 baud.

Once communication has been established using the factorydefaults, the device’s operating parameters may be changedusing the remote computer. The user may also reset the UNITI.D. of the device to any other desired value, as well asresetting the BAUD RATE. Refer to Section 5.3 for importantinformation regarding resetting the BAUD RATE.

5.5 M-SCADA / L-SCADA

The 3300 ACM maintains compatibility with PowerMeasurement’s PC-based power monitoring software pack-ages: M-SCADA and L-SCADA. The 3300 ACM is alsocompatible with the entire family of 3000 series digitalinstrumentation, which includes power meters, powerdemand controllers, and smart transducer interfaces. A singleM-SCADA station can support up to 99 remote sites with atotal of 3168 devices. L-SCADA supports 12 devices distrib-uted across up to 12 sites. Systems are easily expandable, andvery large systems can be built by linking multiple masterstations.

M-SCADA / L-SCADA provides extensive full-colour datadisplay options, automated data handling and system controlfeatures including:

a) Real-time data display for all or part of the powersystem. Full colour, user-configurable system diagramscan be used to give a system-wide display of powerconditions. Real-time and logged data for individualdevices can also be viewed.

b) Display of captured waveforms and harmonicanalysis. M-SCADA / L-SCADA can provide moredetailed power quality analysis to the 63rd harmonicin graphical or tabular formats.*

c) Display of 12-cycle waveform recorder data. Wave-forms for all inputs can be displayed concurrently onthe screen for fault or surge/sag analysis.*

d) Historical trend graphing. M-SCADA / L-SCADAcan display historical, time-interval triggeredsnapshot log data in graphical format.*

e) Detection, annunciation, display and logging ofalarm conditions.*

f) Automatic retrieval and disk archival of data logsfrom remote devices.*

g) Manual control of the on-board relays of all PowerMeasurement devices.*

h) Remote programming of the setup parameters of allPower Measurement devices.

Power Measurement’s proven distributed processing approach topower monitoring guarantees consistently accurate dataretrieval by delegating extensive data acquisition, datalogging, and control capabilities to the remote meter/RTUsites. Less processing requirements at the master stationmeans high reliability and performance. Non-volatile datalogs* ensure data is always retrievable following a temporarypower or communication failure.

* 3300 ACM does not provide this functionality.


5-4 Communications

5.7 THIRD-PARTY SYSTEMCOMPATIBILITY

3300 ACM communications uses an advanced object andregister based open protocol which supports an efficientexception reporting methodology. This allows the 3300 ACMto be easily adapted to third-party PLC, DCS, EMS, andSCADA systems. Currently, the 3300 ACM provides compat-ibility with the Modicon Modbus (see Section 5.8). Thisfeature is provided as part of the basic model 3300 ACM, andis user-selectable using the PROTOCOL parameter.

All data and configuration registers are accessible via commu-nications. All configuration and control operations haveimbedded password protection.

A complete description of the Power Measurement 3300 ACMcommunications protocol is provided in Appendix G.Contact Power Measurement or your local Power Measure-ment representative for complete documentation on the 3300ACM / Modbus communications protocol, or to discuss aspecific application.

5.6 3300 RDT REMOTE DISPLAYTERMINAL

The 3300 RDT is a low cost display terminal which providesremote monitoring of up to thirty-two 3300 ACM's from asingle location using RS-485 communications. The ruggeddesign of the 3300 RDT makes it the ideal display terminal forboth industrial and commercial applications which do notrequire sophisticated SCADA system capabilities.

The 3300 RDT looks and acts identical to the 3300 ACM byoffering the same data presentation formats. The 3300 RDTwill automatically upload and display readings for allmeasured parameters from any connected 3300 ACM meter,with no additional setup required. Since the 3300 RDTprovides all the display functions for each 3300 ACM, all3300 ACMs may be purchased and installed without displaymodules. (NOTE: Field programming of 3300 ACMs withoutdisplay modules must be performed via communicationsusing a portable computer.)

To select which 3300 ACM is to be interrogated, the UNIT I.D.number and BAUD RATE of the meter must be programmedfrom the front panel of the 3300 RDT. No password isrequired.

The 3300 RDT is capable of displaying information for one3300 ACM at a time, communicating at any valid baud ratebetween 300 and 19,200. The 3300 RDT is a master device;therefore, only one 3300 RDT can be used per RS-485 loop.The polling activities of the 3300 RDT can be disabled, toallow other master devices to take control (for field program-ming via communications, etc.) Similar to the 3300 ACM, the3300 RDT on-board operating firmware can be upgradedeasily via the communications port. The 3300 RDT incorpo-rates a 2-part case design identical to the 3300 ACM.

Communications 5-5


Figure 5.8.1 Modbus Communications Connections

NOTE

A 3300 ACM operating in Modbus modewill not be compatible with PowerMeasurement's M-SCADA / L-SCADAsystem.

Hardware Requirements andCommunication WiringMechanical mounting, electrical wiring (other than communi-cations), and general operation of units communicating onthe Modbus are similar to that of the standard 3300 ACM.

The 3300 ACM is connected on an RS-485 network that isinterfaced to the Modbus via an RS-232C to RS-485 converter,such as Power Measurement's COM32TM. A Modicon BM85Bridge/Multiplexer is required between the Modbus andModicon Controller.

A multi-drop topology allows up to thirty-two 3300 ACMs onan RS-485 network to be connected to each of the four BM85Bridge/Mux ports. This allows for up to 128 power meters tobe connected to each BM85 (refer to Figure 5.8.1).

1 SHLD

3 TXD

2 RXD

7 GND

20 DTR

6 DSR

4 RTS

5 CTS

SHLD 1

RXD 2

TXD 3

GND 5

DTR 4

DSR 6

RTS 7

CTS 8

COM32RS-232C Port

Bridge/MuxModbus Port

25-pin MaleD-Type

Connector

9-pin MaleD-Type

Connector

50 feet maximum

Twisted Pairs

Modicon AEG

ModbusPlus

To other Modbus networks (4networks total with 32devices per network)

ModbusPlus

RS-232CPort

ModbusPorts

MODICON 984CONTROLLER

MODICON BM85Bridge/Mux

(DCE)

(DTE)

3300 ACM

To other 3300 ACM devices(32 total possible)

3300 ACM

RS-485Network

COM32tm or COM128tm

RS-232C to RS-485Converter

NOTE

For detailed information regardingconfi-guration of the COM32 orCOM128 inter-faces, refer to themanual for the device.

5.8 MODICON MODBUSCOMPATIBILITY

The 3300 ACM provides compatibility with the ModiconModbus system as a standard feature, selectable from thefront panel. The Modbus communications protocol allowssetup parameters and measured data to be efficiently trans-ferred between a Modicon Programmable Controller andmultiple 3300 ACMs. The 3300 ACM performs Modbuscommunications by emulating a Modicon 984 Controller.

All measured data for the 3300 ACM can be accessed viaModbus, including all real-time, thermal (running) or slidingwindow demand, and minimum/maximum registers.Polarity of power measurements can be determined throughsix polarity registers. All setup parameters are also accessible.Password protection is provided via a special passwordregister location.

The 3300 ACM Modbus protocol supports standard 16 bitregisters, as well as 32 bit extended registers. 32 bit registerswould typically be required only for large energy values (e.g.KWH, etc.) Register size is selectable from the front panel.


5-6 Communications

The cable connecting the Bridge/Mux to the converter is a 9-pin male to 25-pin male serial cable. Refer to Section 2.6 forrequired RS-485 network connections.

NOTE

The Modbus protocol is extremely sensitiveto signal reflections which may be causeddue to an unterminated bus. Refer to Sec-tion 2.6 for information on bus termina-tion.

Setting Communication ParametersWhen using Modbus communications, the range of possibleUNIT ID designations for the 3300 ACM is limited to between1 and 247.

The COM MODE parameter must be set to RS-485.

A setup parameter named PROTOCOL has been provided toselect between Power Measurement and Modbus communica-tions standards. If the 3300 ACM is to be connected to aModbus communications network, the PROTOCOL param-eter should be set to MODBUS.

If PROTOCOL is set to Modbus, the next parameter thatappears is REGISTER SIZE. This parameter determineswhether a 16-bit or an extended 32-bit register is passed incommunications for each function. The default setting is 16BIT.

NOTE

TRAN models (without display/keypadmodule) that are intended for use withModbus communications should be or-dered with the MOD option. For this op-tion, the factory presets the PROTOCOLparameter to MODBUS.

Communications ProtocolCommunications occurs from the Controller via the ModbusPlus network (using MSTR block), across the BM85 to theModbus, and on to the 3300 ACM(s) via the RS-232C / RS-485 converter.

All communications between the BM85 and 3300 ACM(s)conform to a master/slave scheme with the BM85 as themaster and the 3300 ACM(s) as slave(s).

Message Packets SupportedAll registers within the 3300 ACM are accessible as PLC 4xxxxholding registers. The following Modbus commands aresupported:

PRESET MULTIPLE REGISTERS (10H)Allows the Modicon Controller to define all the user-program-mable setup parameters in the 3300 ACM. Registers are alsoprovided to allow the Controller to clear the KW Hour, KVAHour, or KVAR Hour counters of the 3300 ACM.

READ HOLDING REGISTERS (03H)Allows the Controller to read 16-bit or 32-bit real-timemeasured data or setup parameters from the 3300 ACM.

For a detailed specification describing the 3300 ACM Modbuscommunications protocol, refer to the Power MeasurementLtd. document:

3300 ACM / Modicon ModbusSerial Communications Protocol

This document is available upon request from Power Mea-surement or your local Power Measurement representative.

Communications 5-7


5.9 PLC/AB COMPATIBILITY

The PLC/AB option for Power Measurement’s 3300 ACMDigital Power Meter allows access to the Allen-Bradley DataHighway Plus (and Data Highway) through use of the Allen-Bradley Full Duplex DF1 Protocol. The 3300 ACM PLC/ABemulates two commands from the PLC2 command set:Unprotected Read and Unprotected Write. The Full DuplexDF1 protocol allows information and data to be efficientlytransferred between an A-B PLC and a 3300 ACM. ThePLC/AB option allows all real-time parameters, as well askW total demand, kVar total demand, kVA total demand,and Amps average demand parameters for the 3300 ACM, tobe accessed.

Mechanical mounting, electrical wiring (other than communi-cations), and operation of units with the PLC/AB option issimilar to that of the basic 3300 ACM.

Communications wiring requirements are discussed inChapter 2.6, “Communications Connections”.

Hardware Requirements and WiringThe 3300 ACM interfaces to the Data Highway via Allen-Bradley Communication Interface Modules. The two modulesthat the 3300 ACM communicates with are the 1770-KF2Series B Communication Interface Module and the 1785-KESeries B Data Highway Plus RS-232C CommunicationsInterface Module.

MULTI-DROPA multi-drop communications topology allows you to connectup to 128 3300 ACMs to the data highway via one A-Bcommunication interface module using RS-485 communica-tions. A Power Measurement COM32™ or COM128™RS-232C to RS-485 Converter is required for multi-dropsystems (see Figure 5.9.1).

NOTE

Refer to converter manual for detailed in-formation regarding configuration.

Communications ProtocolAll communications between the PLC and 3300 ACM(s)conform to a master/slave scheme. Information and data istransferred between a master PLC and slave 3300 ACM(s).The following message packets are supported:

READ OR WRITE SETUPAllows the PLC to read or define all the user-programmablesetup parameters in the 3300 ACM.

READ LONG OR SHORT REAL-TIME DATAAllows the PCL to read detailed (long) or condensed (short)realtime data measured by the 3300 ACM.

CLEAR KW OR KVAR HOURAllow the PLC to clear the kW hour or kVAR Hour counter ofthe 3300 ACM.

For more information regarding operation with the A-Bcommunications protocol, refer to the Power Measurementdocument: 3300 ACM/Allen-Bradley Serial Communications Protocol.

Figure 5.9.1 PLC/AB Communications Connections

1770-KF2Asynchronous Port

(RS-232C)SHLD 1

TXD 2

RXD 3

RTS 4

CTS 5

DSR 6

GND 7

DCD 8

DTR 11

1 SHLD

2 RXD

3 TXD

4 RTS

5 CTS

6 DSR

7 GND

8 DCD

20 DTR

ConverterRS-232C Port

50 feet maximum

25-pinMale

Connector

25-pinMale

Connector

1785-KERS-232C Port

ConverterRS-232C Port

15-pinMale

Connector

SHLD 1

TXD 2

RXD 3

RTS 4

CTS 5

DSR 6

GND 7

DCD 8

DTR 11

GND 13

1 SHLD

2 RXD

3 TXD

4 RTS

5 CTS

6 DSR

7 GND

8 DCD

20 DTR

25-pinMale

Connector

50 feet maximum


5-8 Communications


Appendix A: Mechanical Dimensions A-1

APPENDIX A

MECHANICAL & MOUNTING DIMENSIONS Display CableThe single cable which connects the DisplayModule to the Base Module is a standard DB25serial communications cable, 6.0 ft. (1.8 m) inlength, with approximate diameter 0.3�� (7.6 mm).

Figure A-1 Display ModuleFront View

1.00’’ Depth(25.4 mm)

4.50’’(114.3 mm)

7.66’’(194.6 mm)

Figure A-2 Display ModuleRear View

0.8’’ (20.3 mm)

Four #10/32 Mounting Studs0.625’’ (16 mm) in lengthDrill four mounting holes0.2’’ (5 mm) diameter

DISPLAY CABLE CONNECTORMinimum required panel cutout

2.3’’ (58.4 mm)

2.00’’(50.8 mm)

3.38’’(85.9 mm)

0.56’’(14.2 mm)

3.83’’ (97.3 mm)

2.14’’ (54.4 mm)

C

3.38’’ (85.9 mm)

Existing ANSI C39.1panel cutout(meter replacement)


A-2 Appendix A: Mechanical Dimensions

MODEL: 3300 ACM

SERIAL NUMBER:

OPTIONS:

ELECTRICAL RATINGS


6703 RAJPUR PLACE

VICTORIA, B.C.

CANADA V8X 3X1

MADE IN

CANADA

+-I32

I31

I22

I21

I12

I11V3

V2

V1

L

NG

OVERALL DEPTHBasic Model:

2.63” (66.8 mm)With P240DC Option:

3.25” (82.6 mm)

TERMINAL STRIPLarge, barrier-style,

7/16’’ (11.1 mm) spacing

Overall Height8.12’’ (206.3 mm)

Mounting Holescenter-to-center

7.67’’ (194.8 mm)

Figure A-4 Terminal Strip Dimensions

Mounting Holes center-to-center5.00’’ (127.0 mm)

Overall Chassis Width5.70’’ (144.8 mm)

Additional Clearancefor Display Cableconnection/routing

3.00’’ (76 mm)Overall Mounting Width

8.70’’ (221.0 mm)

DISPLAYCABLE

4 MOUNTING HOLE SLOTS0.25’’ (6.4 mm) width to fit #10 or #12 bolt

Figure A-3 Base Module Dimensions

Centre-to-centre terminal spacing7/16’’ ( 11.1 mm)

Distance from end of chassis to firstscrew centre on terminal strip

1.25’’ ( 31.8 mm)

Distance of terminal stripscrew centre from edge of

chassis0.73’’ ( 18.4 mm)

Height of terminal stripconnecting position from flange

1.69’’ ( 42.9 mm)

APPENDIX A

MECHANICAL & MOUNTING DIMENSIONS


Appendix B: Firmware Versions B-1

APPENDIX B

3300 ACM FIRMWARE VERSIONS

This following table lists each firmware version release for the3300 ACM and the new features or performance enhance-ments added with each release.

The version number can be identified from the display moduleof the 3300 ACM by entering program mode and going to theFIRMWARE REV parameter under the DIAGNOSTICS group.

If your 3300 ACM is currently using a firmware version olderthan the most recent version listed in the table below, youmay upgrade the software in that unit by contacting yourlocal representative or the manufacturer. Either contact willneed to know the serial number of the 3300 ACM and thecurrent firmware version installed. The serial number can alsobe viewed in the DIAGNOSTICS group.

Most upgrades to the 3300 ACM will require a simpledownload of firmware data into the on-board programmemory inside the unit.

VERSION RELEASE DATE DESCRIPTIONV 1.0.0.1 May 1991 • Initial release.

V1.1.x.x January 1992 • Sliding Window Demand functions offered as options

(previously, only Thermal Demand functions available).

• # OF DMD PERIODS setup parameter added.

• RS-485 port KWH PULSE output function expanded to provide eitherpulse or transition output. PULSE FORMAT and PULSE DURATION setupparameters added.

• Modicon Modbus compatibility added as standard feature. PROTOCOLand REGISTER SIZE setup parameters added. AMPS SCALE rangeincreased to 30,000.

• Power factor polarity via communications modified: Leading PF = positivenumber, Lagging PF = negative. (Note: This change does not affect frontpanel LEAD/LAG display indication.)

• Manual sliding window demand synchronization added.

• All real-time demand parameters are now reset when Min/Max reset.

V1.2.x.x February 1993 • FORMAT parameter added to allow customization of phase labels anddecimal format.

• CONTRAST/ANGLE parameter added for LCD display.

• CLEAR STATUS? parameter added to allow clearing of diagnostic flags.

• Auto Function Cycling Mode added. 4-wire Wye / 2½ element connectionmode (3 WIRE WYE) and demonstration mode (DEMO) added to VOLTSMODE options.

V.1.2.2.x November 1993 • Decimal display capability and high resolution communication packetformat added.

V.1.3.x.x September 1994 • Added ability to change protocol from PML to Modbus viacommunications.

V.1.3.1.x April 1995 • Demand calculations are reset when any operating parameter is changed(e.g. - volts scale, current scale, demand, period, etc.)

• Demand min/max comparisons made after demand has reached 99% ofits' steady state value

• Power factor sign determined independently on each phase.


Appendix C: Technical Specifications C-1

APPENDIX C3300 ACM TECHNICAL SPECIFICATIONS

ACCURACY, RESOLUTION, & RANGE

INPUT RATINGS

NOTES: 11111 Optional measurement. 2 2 2 2 2 Reads in k (i.e. x 1000) for readings over 9,999. 33333 @50.0 Hz or @60.0 Hz @ 25°C/77°F.

E95810 LR 57329 NOTE: P120DC and P240DC options are not currently CSA orUL approved.

Type Basic or Optional Description

Voltage Inputs: Basic Model: 120 VAC line-neutral / 208 VAC line-line to 347 VAC line-neutral / 600VAC line-line nominal full scale input (programmable).Overload withstand: 600 VAC continuous, 1500 VAC for 1 SecInput impedance: 1 Megohm

Current Inputs: Basic Model: 5.000 Amps AC nominal full scale input1AMP Option: 1.000 Amp AC nominal full scaleAll Options: Overload withstand: 15 Amps continuous, 300 Amps for 1 sec.

Input impedance: 0.002 ohm Burden: 0.05 VA

Power Supply: Basic model: 108 to 132 VAC / 47 to 66 Hz @ 0.25 AmpP240 Option: 216 to 264 VAC / 47 to 66 Hz @ 0.125 AmpP24 Option: 22 to 27 VDC @ 0.3 AmpP120DC Option: 85 to 132 VAC / 47 to 440 Hz or 110 to 170 VDC @ 0.1 AmpP240DC Option: 85 to 264 VAC / 47 to 440 Hz or 110 to 340 VDC @ 0.1 Amp

Operating Temperature: All models: 0oC to 50oC (32oF to 122oF) ambient air

Storage Temperature: All models: –30oC to +70oC (-22oF to +158oF)

Humidity: All models: 5 to 95 percent, non-condensing

Shipping Weight: Basic Model: 3.3 kg, 7 lb. 4 oz.

Shipping Dimensions: All models: 38 x 25 x 18 cm, 15 x 9.8 x 7.1 inches

Voltage, Current, and Power inputs all pass the ANSI/IEEE C37.90A-1989 surge withstand and fast transient tests.Complies with FCC/DOC emmisions standard.

Accuracy3 (% of Full Scale)

Parameter Standard -HIACC Option Resolution RangeVolts & Volts Demand11111 0.5 % 0.25 % 0.1 % 0 - 999,99922222

Amps & Amps Demand11111 0.5 % 0.25 % 0.1 % 0 - 32,000

kW & kW Demand11111 1.0 % 0.5 % 0.1 % 0 - 999,999

kVAR11111 & kVAR Demand11111 1.0 % 0.5 % 0.1 % 0 - 999,999

kVA11111 & kVA Demand11111 1.0 % 0.5 % 0.1 % 0 - 999,999

Power Factor11111 & PF Demand11111 2.0 % 1.0 % 1.0 % -0.6 to 1.0 to +0.6

Frequency1 1 1 1 1 & Freq. Demand11111 0.2 Hz 0.2 Hz 0.1 Hz 45 to 70 Hz

kWh, kVARh11111 & kVAh11111 1.0 % 0.5 % 1 kWh, kVARh, or kVAh 0 - 999,999,999

Volt-Hours11111 1.0 % 0.5 % 1 Hour 0 - 999,999,999


C-2 Appendix C: Technical Specifications


Appendix D: Model/Ordering Information D-1

HARDWARE OPTIONSStandard Hardware Features:• 347VAC l-n/600 VAC l-l full scale voltage inputs• Display / keypad module• 5 Amp full scale current inputs• RS-485 comm. port• Powered by 108 to 132 VAC/47 to 66 Hz @ 0.25 A

Standard Measured Parameters:• 3-phase line-to-neutral voltage, per phase and average• 3-phase line-to-line voltage, per phase and average• 3-phase current, per phase and average• kW Total of all phases• kWh Total of all phases

BASIC MODEL FEATURESMOD Preset to Modbus communications (TRAN models

only)P240 Powered by 216 to 264 VAC/47 to 66 Hz @ 0.125 AP24 Powered by 22 to 27 VDCP120DC Powered by 85 to 132 VAC or 110 to 170 VDC*P240DC Powered by 85 to 264 VAC or 110 to 340 VDC*1AMP 1 Amp nominal full scale current inputsTROP Tropicalization (conformal coating) treatmentHIACC: High accuracy version (see specifications)

Specify input voltage: 120, 277, or 347 VAC

*see note below

APPENDIX D3300 ACM MODEL/ORDERING INFORMATION

NOTE

In situations where the power supply to the 3300 ACM might be unstable, the P120DC or P240DC powersupply option should be used. These power supplies have much better immunity to power disturbances thanthe standard linear power supply provided by the basic model or P240 option. Potentially unstable powerconditions include situations where:

1) there are frequent power disturbances or interruptions

2) the 3300 ACM is powered from a genset

3) the frequency can vary outside the specified limits of the basic model power supply or P240 option powersupply

…continues (see next page for Measurement options)


D-2 Appendix D: Model/Ordering Information

ORDERING EXAMPLE

ORDERING MEASUREMENT OPTIONS

SLIDING MIN. SLIDING MAX. SLIDINGMEASUREMENT WIN. DEMAND WIN. DEMAND WIN. DEMANDI avg 98 99 100

kW total 101 102 103

kVAR total 104 105 106

kVA total 107 108 109

1. Measurement options shown in reverse print in thechart are basic features of the 3300 ACM.

2. A maximum of 20 additional optional measuredparameters may be ordered. Note that some optionsrepresent per phase groupings of 3 measured param-eters. Specify each option using the associated numbercode.

3. Measurements marked by an asterisk (*) are notavailable when using the 3300 ACM in a 3-wire Deltaconfiguration.

3300ACM -P240 -HIACC: 277 -37 -80 -85 -103

Basic Model Hardware Options Measurement Options

MEASUREMENT IMPORT EXPORT TOTALkW Hours 91 92 93

kVAR Hours 94 95 96

kVA Hours n/a n/a 97

* Volt-Hours n/a n/a 110

MEASUREMENT OPTIONS

*

*

*

*

*

*

TOTAL PARAMETERS I NSTAN- MINIMUM MAXIMUM THERMAL MIN. THERMAL MAX. THERMALMEASUREMENT PER OPTION TANEOUS INSTANT. INSTANT. DEMAND DEMAND DEMANDV an, bn, cn (per phase) 3 01 02 03 04 05 06

V average, line-to-neutral 1 07 08 09 10 11 12

V ab, bc, ca (per phase) 3 13 14 15 16 17 18

V average, line-to-line 1 19 20 21 22 23 24

I a, b, c (per phase) 3 25 26 27 28 29 30

I average 1 31 32 33 34 35 36

kW a, b, c (per phase) 3 37 38 39 40 41 42

kW total 1 43 44 45 46 47 48

kVAR a, b, c (per phase) 3 49 50 51 52 53 54

kVAR total 1 55 56 57 58 59 60

kVA a, b, c (per phase) 3 61 62 63 64 65 66

kVA total 1 67 68 69 70 71 72

PF a, b, c (per phase) 3 73 74 75 76 77 78

PF total 1 79 80 81 82 83 84

Frequency 1 85 86 87 88 89 90


Appendix E: Warranty and Registration E-1

APPENDIX E

WARRANTY & REGISTRATION

1 WARRANTY

Power Measurement Ltd. warrants its products to be freefrom manufacturing defects for three years from the dateof shipment from the factory. The manufacturer willrepair or replace defective equipment F.O.B. point ofmanufacture for up to three years provided the equipmenthas been installed, wired, programmed, and operated inaccordance with the manufacturer’s instruction manualincluded with each unit, and the applicable sections of theElectrical Code. The warranty does not include liabilityfor any effects caused by Power Measurement productfailure.

2 PRODUCT RETURNPROCEDURE

The following procedure must be strictly adhered to whenreturning any Power Measurement product to the factoryfor the purpose of repair, replacement, credit, upgrade,recalibration, or for any other reason.

1. Contact Power Measurement or your local PowerMeasurement Sales Representative and obtain aReturn Merchandise Authorization (RMA) number priorto shipment of any unit back to the manufacturer. Beprepared to provide the product’s model number,serial number, and the reason for returning the unit.Units received without prior authorization will notbe accepted under any circumstances.

2. If the unit is being returned for repair, replacement, orupgrade a product return report should be completedand included with the unit. The information pro-vided should include:

a) A functional description of the unit defect orfailure and the electrical/environmental condi-tions at the time of failure. This will significantlyreduce repair/upgrade time (and cost, if war-ranty has expired). If the unit is being returnedfor an upgrade, recalibration or other modifica-tion, list the requirements.

b) The RMA number issued by Power Measurement,the serial number of the unit, the company nameand address, the name of the person filling outthe report, and the date.

c) IMPORTANT: The return address to which theunit is to be shipped following servicing.

3. Pack the unit safely, preferably in the original ship-ping carton, and include the detailed report describedabove. The RMA number must be clearly markedon the outside of the box.

4. A packing slip must be attached to the outside of thebox which includes the points of origin and destina-tion, a description of contents, and the reason forreturn. Examples: For Repair and Return, or Returnedfor Credit. There should be no need to declare a value.

5. Ship PREPAID to the appropriate address below.Power Measurement will not accept C.O.D. ship-ments. If the unit is still under warranty, PowerMeasurement will pay the return shipping charges.

For shipments originating in the U.S.A.:

Power Measurement Ltd.c/o VICTORIA CUSTOMS BROKERS4131A Mitchell WayBellingham, WA 98226

For shipments originating overseas:

Power Measurement Ltd.2195 Keating Cross RoadSaanichton, BC V8M 2A5

CUSTOMS CLEARANCELivingston International Inc.Telephone: (250) 388-4435

For shipments originating in Canada:

Power Measurement Ltd.2195 Keating Cross RoadSaanichton, BC V8M 2A5

3 REGISTRATION

Please complete and mail the enclosed Warranty Registra-tion card immediately. This will allow us to add you toour mailing list, to keep you up to date on the latestproduct firmware releases and new feature offerings.

Your comments and suggestions for product improvementand feature additions are welcome.


E-2 Appendix E: Warranty and Registration


Appendix F: Troubleshooting F-1

A number of problems can cause the 3300 ACM not tofunction properly. This appendix lists a number of symptoms,and explains how to correct them.

1. If the display does not operate:

a) check that the correct voltage is available to thepower supply (L/+ and N/- connections on theterminal strip). The required voltage will depend onthe power supply option of the unit.

b) confirm that the G terminal is connected directly toground.

c) check the display cable connection between thedisplay module and the base module.

d) disconnect the cable connection between the displaymodule momentarily, then reconnect.

If the above steps do not solve the problem, perform thefollowing:

a) As a diagnostic test, turn both the 3300 ACM off(disconnect power) and the computer off for at leastten seconds. Apply power again and check if theunit powers up correctly.

b) Contact Power Measurement or your local PowerMeasurement representative and report the problemand results of the test.

2. If the voltage or current readingsare incorrect:

a) check that the voltage mode is properly set for thegiven wiring.

b) check that the voltage and current scales areproperly set.

c) make sure the G terminal is properly grounded.

d) check the quality of the CT’s and PT’s being used.

e) make the following voltage tests:

i) V1, V2, V3 to G should be reasonably balanced,and no greater than 347 VAC.

ii) G to switchgear earth ground should be 0 V.

3. If the kW or power factor readings are incorrect butvoltage and current readings are correct:

Make sure that the phase relationship between voltage andcurrent inputs is correct by comparing the wiring with theappropriate wiring diagram. Note that Power Measurement’s M-SCADA, L-SCADA or PowerView PC-based software can beused to verify PT and CT sequence and polarity by analyzingthe captured voltage and current waveforms for each phase.

4. If RS-485 communication does not work:

a) check that the baud rate of the host computer/PLCis the same as that of the 3300 ACM.

b) check that the COM MODE parameter is set to RS-485 (not KWH PULSE).

c) check that the number of data bits is set to 8, withone stop bit and no parity.

d) check that the RS-232C to RS-485 Converter isconfigured correctly and that it is passing data.

e) check all communications wiring (Chapter 2).

If the above steps do not solve the problem, perform thefollowing:

a) As a diagnostic test, turn both the 3300 ACM off(disconnect power) and the computer off for at leastten seconds. Apply power again and check if thecommunications operate successfully.

b) Contact Power Measurement or your local PowerMeasurement representative and report the problemand results of the test.

If the symptom persists after performing the specified steps,or if the symptom is not listed above, contact your local PowerMeasurement representative or the technical support /customer service department of Power Measurement (see thefront of this manual).

APPENDIX F

TROUBLESHOOTING


F-2 Appendix F: Troubleshooting


Appendix G: Serial Communications Protocol G-1

APPENDIX G

SERIAL COMMUNICATIONS PROTOCOL

NOTE

The information contained in this docu-ment is believed to be accurate at the timeof its publication; however, Power Mea-surement Ltd. assumes no responsibilityfor any errors which may appear here andreserves the right to make changes withoutnotice.

1 INTRODUCTIONThis document details the Power Measurement serial commu-nications protocol used to pass commands, information anddata into and out of the model 3300 ACM Power Meter.Provided is all the information necessary for a 3rd party OEMto develop in-house software to communicate with a 3300ACM.

Only the basic Power Measurement protocol is described here.For detailed information regarding the 3300 ACM / Modbuscommunications protocol, contact Power Measurement oryour local representative.

1.1 PURPOSE

The purpose of the communications protocol is to allowinformation and data to be efficiently transferred between acentral data collection station (Master Station) and a 3300ACM Power Meter. This includes:

1) Allowing configuration and interrogation of all 3300ACM power meter setup parameters from the Masterstation.

2) Allowing interrogation of all data measured by a 3300ACM power meter.

1.2 REVISIONS

May 24, 1991 Initial release.

October 1, 1993 Decimal accuracy and high resolutionrequest packets added.

2 DETAILED DESCRIPTION

2.1 PROTOCOL GROUND RULES

The following rules define the protocol for informationtransfer between the RS-485 loop controller and othercomponents of the RS-485 serial communications loop.

1) All communications on the RS-485 loop conforms to aMASTER/SLAVE scheme. In this scheme, informationand data is transferred between a single MASTER loopcontroller and up to 32 SLAVE monitoring devices.

2) The MASTER will initiate and control all informationtransfer on the RS-485 communications loop.

3) Under no circumstances will a SLAVE device initiate acommunications sequence.

4) All communication activity on the RS-485 loop occurs inthe form of “PACKETS”, a packet being simply a serialstring of 8 bit bytes. The maximum number of bytescontained within one packet is 255.

The bytes that comprise a packet consist of standardasynchronous serial data transmitted with 8-bits perdata byte, no parity and one stop bit. The serial datastreams are generated using equipment similar to thatused for RS-232C.

5) All transmissions on the RS-485 loop can be divided intotwo types of packet activity:

i) Master to Slave transmissions

ii) Slave to Master transmissions

These two packet types are distinguished via a“sync” byte that is transmitted as the first byte ofevery packet.

For Master to Slave transmissions,

sync = 00010100B = 14H

For Slave to Master transmissions,

sync = 00100111B = 27H

6) In the case where the Master or any Slave device receivesa packet that contains an unknown command, thepacket shall be ignored and no further response will bemade by the receiving unit.


G-2 Appendix G: Serial Communications Protocol

2.2.3 ADDRESS INFORMATION FIELD

The Address Information field is fixed in length and containsthe following two sub-fields:

1) SOURCE ADDRESS (2 Bytes)

These two bytes contain the address of the device fromwhich the packet originated.

2) DESTINATION ADDRESS (2 Bytes)

These two bytes contain the address of the device towhich the packet is being sent.

2.2.4 DATA FIELD

The Data Field will vary in length (0 to 251 Bytes) accordingto the type of message contained within the packet.

DATA REGISTERSAll information passed to and from the meter within the datafield is in the form of registers. Each register is represented by4 bytes. Three of the bytes contain the metering data or setupdata. Byte 4 of each data register represents the low order byteof the 16 bit address where the register is located.

BYTE 1 BYTE 2 BYTE 3 BYTE 4

Data Bits Data Bits Data Bits Low order register 0 to 7 8 to 15 16 to 23 address byte

For example, a 4 byte value of 3C,06,00,21 hex would indicatethat register 0021hex (which is total kW) has a value of00063C hex (or 1596 kW in decimal).

REGISTER ADDRESSESEach piece of metering data, as well as each setup parameter,is assigned a unique 16 bit register address. For example, totalkW is located at register address 0021 hex (or 33 decimal).The current scale parameter is located at 0A03 hex (or 2563decimal).

The low order byte of the register address is represented byByte 4 of the register. The high order byte of the addressrepresents the register page.

REGISTER PAGESData registers are grouped in pages. The most significant (highorder) byte of the register address indicates the page withinwhich the register resides. The page in which a register islocated is an indication of the nature of that register:

Page 0: real time metering data

Page 1: minimum values

Page 2: maximum values

Page 10: meter setup parameters

A complete list of register addresses is provided in Figures G-3a and G-3d.

2.2 DESCRIPTION OF THEPACKET STRUCTURE

Every packet is composed of five fields:

1) The Message Establishment Field

2) The Control Information Field

3) The Address Information Field

4) The Data Field with optional High-Resolution ResultRequest Flag

5) The Message Termination Field

2.2.1 MESSAGE ESTABLISHMENT FIELD

The Message Establishment field is fixed in length andcontains the following two sub-fields:.

1) SYNC (1 Byte)

The Sync sub-field contains a single byte to indicatewhether the packet is being transmitted from the Masterloop controller to a Slave device or from a Slave device tothe Master loop controller.

For a Master to Slave transmission, sync = 14 Hex

For a Slave to Master transmission, sync = 27 Hex

2) DEVICE TYPE (1 Byte)

The Device Type sub-field contains a single byte toindicate the make and model of the Slave device used.

For packets sent to/by the model 3300 ACM powermeter, the Device Type sub-field is always set to 253decimal = FD Hex.

2.2.2 CONTROL INFORMATION FIELD

The Control Information field is fixed in length and containsthe following two sub-fields:

1) MESSAGE TYPE (1 Byte)

This byte is used to distinguish between the varioustypes of messages, commands and data that are con-tained by the packet.

2) PACKET LENGTH (1 Byte)

This byte indicates the number of bytes that are con-tained within the Address Information and Data fieldsof the packet.



For example, if the 3300 ACM is responding to a readcommand for which the requested register is the current inputscale of the meter at address 0A03 hex, the first command inthe data field from the 3300 ACM will be to select page 10 (0Ahex):

0A,00,00,00

Change to Command writtennew page 10 to register 0

Once page 10 has been indicated, the requested data on thatpage will be sent:

88,13,00,03

Requested data is Low order data001388 hex register address 03

The data received by the Master Station is a current scalevalue of 001388 hex (5000Amps decimal).

2.2.5 MESSAGE TERMINATION FIELD

The Message Termination Field is fixed in length and containsonly 1 byte. This byte is an eight bit error code used to detectpackets that have been corrupted during transmission.

The error code is an eight bit Longitudinal Redundancy Check(LRC) which is complemented prior to transmission.

The LRC is calculated by a simple arithmetic sum over allpreceding message bytes contained within the packet with theexception of the eight bit sync sub-field. The sum is thencomplemented to yield the LRC byte.

The data register contains only the least significant (loworder) register address byte. A special command is used toaccess registers on different pages. In this way, the entiredata field will be composed of specific register values inter-spersed with page change commands.

REGISTER PAGING: REGISTER WRITE COMMANDSThe write command will always begin writing on page 0(zero). Register writes from the Master Station to the 3300ACM registers contain the low order register address byte inByte 4 of the register.

In order to change pages, the new page number must bewritten into Byte 1 of register 0 of the current page. The onlyregisters which can be written to are on page 10 (meter setupparameters), so the first data write command must always bea page change to page 10.

For example, to change the current input scale of a meter theaddress 0A03 hex must be written to. To select page 10 (0Ahex), the first data command must be:

0A,00,00,00

Change to Command writtennew page 10 to register 0

Once page 10 has been selected to change the current scale toa value of 001388 hex (or 5000Amps decimal), the seconddata command must be:

88,13,00,03

Write new data Write to low order001388 hex register address 03

REGISTER PAGING: REGISTER READ COMMANDSThe 3300 ACM response to a read command will alwaysbegin on page 0 (zero). If the first valid requested register isnot on page 0, a page change will occur immediately. Similar tothe page change command described above, the new pagenumber is written into Byte 1 of register 0 of the current page.

The response data fields will contain the low order registeraddress byte in Byte 4 of the register. All valid registers onthat page will be sent, then the 3300 ACM will change to thenext page by sending a page change command.

This will repeat until all requested data has been sent, or thepacket is full.



2.4 NETWORK TIMINGCONSIDERATIONS

Network timing for the transfer of packets between units onthe RS-485 loop must conform to the following rules.

1) The time between the end of a MASTER STATIONmessage request packet and the beginning of a SLAVESTATION message response packet must not be less than5 milliseconds.

T response min = 5 milliseconds

This is to provide the MASTER STATION with enoughtime to prepare for reception of the message responsepacket from the SLAVE STATION.

2) The time between the end of a MASTERSTATION message request packet and the beginning of aSLAVE STATION message response packet must notexceed 500 milli-seconds.

T response max = 500 milliseconds

Note that this is typically 100 millisecondsfor the 3300 ACM.

3) The minimum time between the end of any MASTERSTATION message packet and the beginning of the nextMASTER STATION packet is device dependent.

T master min = [device dependent]

This is equal to 100 milliseconds for the3300 ACM.

4) The minimum time between the end of a SLAVE STA-TION response packet and the beginning of the nextMASTER STATION message packet is device dependent.

T slave min = [device dependent]

Note that this is equal to 100 milliseconds for the 3300ACM.

5) The maximum time between any two data bytes within apacket must not exceed 50 milliseconds.

T byte max = 50 milliseconds.

Note that this is typically less than 1 millisecond for the3300 ACM.

6) It is recommended that all Master station packet trans-missions be prefixed with two null bytes to ensure thatthe RS-485 data bus is stable before the sync byte istransmitted.

2.3 BROADCAST PACKETS

Provisions have been made for the use of broadcast com-mands within the RS-485 data transfer protocol. The purposeof this is to allow all Slave devices to receive the same com-mand from the Master station. This feature is very useful insituations such as initial setup where all 3300 ACM metershave the same setup parameters.

When broadcast packets are transmitted by the Master loopcontroller, all Slave devices will receive and perform the packetcommand but will not send a response packet. This is toavoid the possibility of having more than one Slave Devicerespond at one time. The Master Station must ensure thatcommands sent via the broadcast mode do not attempt toinvoke a response from the Slave Devices.

To send broadcast commands to all 3300 ACM units on anRS-485 loop, the Device Type Sub-field must be 253 decimal orFD hex, and the destination unit address of the ADDRESSINFORMATION field must be set to 0000 Hex.

Only when the destination address is set to zero will broad-cast command packets be performed by the receiving 3300ACM unit.



Figure G-1 Read Registers Packet

3 PACKET COMMUNICATIONSThis section details all packet communications into and out ofthe model 3300 ACM power meter. There are only twodifferent packet types: one for reading the registers and theother for writing them.

Section 3.1 discusses the command packet to read theregisters, and the response packet issued by the meter.

Section 3.2 discusses the command packet to write data to theregisters, and the acknowledgement packet issued by themeter.

3.1 READ REGISTERS PACKET

This request packet is sent by the Master Station (the PC) torequest that the 3300 ACM respond with all valid registerswithin the range given by Start register and End register.Typically no password is required to read the registers. In thiscase any number may be placed in the password location ofthe packet. There are, however, two cases where the correctpassword is required.

1) To read a protected register. Presently the only protectedregister is the register where the meter password is held.

2) If the PROTECTED READ ONLY register (address 0A10hex) has been set. In this case the password must becorrect to read any register.

Only valid registers will be sent in the response packet.Registers for which the meter is not equipped, or do not existfor a given voltage mode will not be sent.

NOTES:1. Registers are 4 bytes with 1 byte register address LSB field and 3 bytes data field.2. A register address value of 0 indicates a page change to the page given in the data field.3. The maximum number of registers in a response packet is 61. If there are more valid registers in the requested range the last register

will be change to page FF.

READ REGISTER PACKET(Master to 3300 ACM)

14 (1 byte)

FD (1 byte)

83 (Read Registers command) (1 byte)

Length (1 byte)

Master address (2 bytes)

3300 address (2 bytes)

Password (2 bytes)

Start Register requested (2 bytes)

End Register requested (2 bytes)

LRC Checksum (1 byte)

READ RESPONSE PACKET(3300 ACM to Master)

27 (1 byte)

FD (1 byte)

83 (Read Registers command) (1 byte)

Length (1 byte)



Device Type (2 bytes)

Number of Registers sent (2 bytes)

1st Register in Range (4 bytes)

2nd Register in Range (4 bytes)

... ...

... ...

LRC Checksum (1 byte)



ACCESS TO HIGH-RESOLUTION RESULTSTo access the high-resolution values through communica-tions, a High-Resolution Result Request Flag must be appended tothe end of the Data Field. The Request Flag is a single bytecontaining the value FF hex.

If the meter is equipped with firmware revision 1.2.2.0 orgreater, it will respond to a high-resolution Read Registercommand as it would for a regular Read Registers command,except that a special Page 0 Register 03 will be the first registerreturned. This register will contain the following information:

03,vv,aa,pp

where 03 = register number

vv,aa,pp = flags for high-resolution Volts,Amps, and power.

If the Volts flag equals FF hex, any subsequent Volts registerslisted previously will be passed through communications tentimes their actual value for the current packet only. The aa flag willsimilarly indicate that any subsequent Amps registers listedabove will be passed through communications ten times theiractual value. If the pp flag is FF hex, this indicates thatsubsequent power registers listed previously will be passed asW, VA or VAR rather than KW, KVA or KVARS.

NOTE

The Page 0 Register 03 can only be read from a3300 ACM by including the High-Resolu-tion Request Flag to a Read Registers re-quest packet. This allows the 3300 ACM toremain completely compatible with earliercommunications packages which do notrequest high-resolution data (e.g. M-SCADA versions previous to release 4.1).Refer to the documentation for your com-munications package to see if the high-resolution feature is supported.

Similarly, 3300 ACMs equipped with firm-ware previous to version 1.2.2.0 will simplyignore the High-Resolution Request Flag,and return a regular response packet. Theabsence of the special Page 0 Register 03 indi-cates that regular results are being returnedfor all registers.

High-Resolution Display Option

HIGH-RESOLUTION REGISTERSBeginning with firmware release 1.2.2.0, the 3300 ACM iscapable of communicating high-resolution results if theDISPLAY DECIMALS parameter is set to YES.

High-resolution results are available for the following Page 0(real-time) registers:

• 10, 11, 12, 13 (Van, Vbn, Vcn, Vln-average)

• 14, 15, 16, 17 (Vab, Vbc, Vca, Vll-average)

• 20, 21, 22, 23 (Ia, Ib, Ic, I-average)

• 33 (KW total)

• 30, 31, 32 (KWa, KWb, KWc)

• 34, 35, 36, 37 (KVARa, KVARb, KVARc, KVAR total)

• 42, 43, 44, 45 (KVAa, KVAb, KVAc, KVA total)

NOTE

High-resolution results are not available forany minimum, maximum, demand, de-mand min/max, or energy (hours) mea-surements.

HIGH-RESOLUTION READINGSIf Volts Line-to-Neutral Total is under 1000 V, or Volts Line-to-Line Total is under 1732 V, the meter internally scales theinstantaneous voltage reading up by ten.

Amps are always internally scaled up by ten.

If KVA Total is under 40,000 (40 KVA), the meter scales allinstantaneous power values up by 1000. This effectivelyconverts power readings to Watt, VA, and VAR units.

All increased precision values described above are availablethrough communications.



3.2 WRITE REGISTERS PACKET

This packet allows the master to program the setup param-eters of a 3300 ACM meter. In order to write to a meter themeter password must be known and placed in the passwordlocation of the write registers packet.

4 REGISTER LISTThe basic model 3300 ACM is equipped with the followingregisters:

10,11,12,13,14,15,16,17,20,21,22,23,33,54,55

These represent Van, Vbn, Vcn, Vln average, Vab, Vbc, Vca,Vll average, Ia, Ib, Ic, I average, total kW, total kW hours andtotal GW hours. In addition, the 3300 ACM may beequipped with any of the parameters listed as optional inFigures G-3a to G-3c. A 3300 ACM may contain up to 40different parameters.

The page 10 setup registers are common to all 3300 ACMmeters and are not counted as part of the maximum 40possible parameters. Figures G-3a to G-3e list all possibledata registers. Figure G-3d lists the 3300 ACM setupregisters.

Figure G-2 Write Registers Packet

NOTES1. There is no requirement to specify all registers, or to assign them in any particular order. For example, if you wish to change only the Amp scale, a packet

may be sent with only that constant.2. A write to a protected Read/Write register requires that the password stored in the device be sent in the write packet or the write command will be ignored.

For a write to an unprotected Read/Write register the password is not required. At present, all 3300 registers are protected.3. The device responds with an acknowledge packet. If all registers were successfully written to the device will respond with 0xFFH in the Ack/Nack byte

otherwise it will respond with 0x00H in the Ack/Nack byte.

WRITE REGISTER PACkET(Master to 3300 ACM)

14 (1 byte)

FD (1 byte)

81 (Protected write command) (1 byte)

Length (1 byte)



Password (2 bytes)

Number of Registers in Packet (2 bytes)

1st Register (4 bytes)

2nd Register (4 bytes)

...

nth Register

...

LRC (1 byte)

WRITE RESPONSE PACKET(3300 ACM to Master)

27 (1 byte)

FD (1 byte)

81 ([Protected] write command) (1 byte)

Length (1 byte)



Device Type (2 bytes)

Ack/Nack (1 byte)

LRC (1 byte)



Figure G-3a 3300 ACM Data Registers - Part I

REAL TIME PARAMETERS: PAGE 0

0 0 WO PAGE Register Basic0 3 RO High-Resolution Flag Basic

0 10 RO Van Basic1

0 11 RO Vbn Basic1

0 12 RO Vcn Basic1

0 13 RO Vln average Basic1

0 14 RO Vab Basic0 15 RO Vbc Basic0 16 RO Vca Basic0 17 RO Vaverage (l-l) Basic0 20 RO Ia Basic0 21 RO Ib Basic0 22 RO Ic Basic0 23 RO Iaver Basic0 30 RO kW Phase A Opt.1

0 31 RO kW Phase B Opt.1

0 32 RO kW Phase C Opt.1

0 33 RO kW TOTAL Basic0 34 RO kVAR Phase A Opt.1

0 35 RO kVAR Phase B Opt.1

0 36 RO kVAR Phase C Opt.1

0 37 RO kVAR Total Opt.0 38 RO Power Factor A Opt.1

0 39 RO Power Factor B Opt.1

0 40 RO Power Factor C Opt.1

0 41 RO Power Factor Total Opt.0 42 RO kVA Phase A Opt.1

0 43 RO kVA Phase B Opt.1

0 44 RO kVA Phase C Opt.1

0 45 RO kVA Total Opt.0 47 RO Freq on V1 Opt.0 50 RO kWH Import Opt.0 51 RO GWH Import Opt.0 52 RO kWH Export Opt.0 53 RO GWH Export Opt.0 54 RO kWH Total (kWH imp+exp) Basic0 55 RO GWH Total Basic0 60 RO kVARH Import Opt.0 61 RO GVARH Import Opt.0 62 RO kVARH Export Opt.0 63 RO GVARH Export Opt.0 64 RO kVARH Total Opt.0 65 RO GVARH Total Opt.0 70 RO kVAH Opt.0 71 RO GVAH Opt.0 72 RO Volt hours Opt.

Thermal Demand ValuesThe Thermal demand values are a running average of the real time parameterover a user specified time period from1 min. to 9999 min., calculated using thermal averaging.

0 110 RO Van Dmd Opt.0 111 RO Vbn Dmd Opt.0 112 RO Vcn Dmd Opt.0 113 RO Vln aver Dmd Opt.0 114 RO Vab Dmd Opt.0 115 RO Vbc Dmd Opt.0 116 RO Vca Dmd Opt.0 117 RO Vaverage (l-l) Dmd Opt.0 120 RO Ia Dmd Opt.0 121 RO Ib Dmd Opt.0 122 RO Ic Dmd Opt.0 123 RO Iaver Dmd Opt.0 130 RO kW a Dmd Opt.1

0 131 RO kW b Dmd Opt.1

0 132 RO kW c Dmd Opt.1

0 133 RO kW total Dmd Opt.0 134 RO kVAR a Dmd Opt.1

0 135 RO kVAR b Dmd Opt.1

0 136 RO kVAR c Dmd Opt.1

0 137 RO kVAR total Dmd Opt.0 138 RO PF a Dmd Opt.1

0 139 RO PF b Dmd Opt.1

0 140 RO PF c Dmd Opt.1

0 141 RO PF total Dmd Opt.0 142 RO kVA a Dmd Opt.1

0 143 RO kVA b Dmd Opt.1

0 144 RO kVA c Dmd Opt.1

0 145 RO kVA total Dmd Opt.1

0 147 RO Frequency Dmd Opt.

Sliding Window Demand ValuesSliding window demand is a calculation of the demand as measured and billedby the power utility, using either a fixed or rolling window technique.

0 180 RO Amps Demand Average Opt.0 181 RO kW Demand Total Opt.0 182 RO kVAR Demand Total Opt.0 183 RO kVA Demand Total Opt.

PG # REG # REG DESCRIPTION BASIC/TYPE (b) OPTIONAL




Figure G-3b 3300 ACM Data Registers - Part II

Notes:1. 1 Available in Wye mode only2. Register Types: RO = Read Only

WO = Write OnlyRW = Read/write



Minimum Thermal Demand Values

1 110 RO Van Dmd Opt.1 111 RO Vbn Dmd Opt.1 112 RO Vcn Dmd Opt.1 113 RO Vln aver Dmd Opt.1 114 RO Vab Dmd Opt.1 115 RO Vbc Dmd Opt.1 116 RO Vca Dmd Opt.1 117 RO Vaver (l-l) Dmd Opt.1 120 RO Ia Dmd Opt.1 121 RO Ib Dmd Opt.1 122 RO Ic Dmd Opt.1 123 RO Iaver Dmd Opt.1 130 RO kW a Dmd Opt.1












1 145 RO kVA total Dmd Opt.1 147 RO Frequency Dmd Opt.

Minimum Sliding WIndow Demand Values


MINIMUM VALUES: PAGE 1

1 0 WO PAGE Register Basic

Minimum Real Time Values

1 10 RO Van Opt.1 11 RO Vbn Opt.1 12 RO Vcn Opt.1 13 RO Vln average Opt.1 14 RO Vab Opt.1 15 RO Vbc Opt.1 16 RO Vca Opt.1 17 RO Vaverage (l-l) Opt.1 20 RO Ia Opt.1 21 RO Ib Opt.1 22 RO Ic Opt.1 23 RO Iaver Opt.1 30 RO kW a Opt.1

1 31 RO kW b Opt.1

1 32 RO kW c Opt.1

1 33 RO kW total Opt.1 34 RO kVAR a Opt.1

1 35 RO kVAR b Opt.1

1 36 RO kVAR c Opt.1

1 37 RO kVAR total Opt.1 38 RO PF a Opt.1

1 39 RO PF b Opt.1

1 40 RO PF c Opt.1

1 41 RO PF total Opt.1 42 RO kVA a Opt.1

1 43 RO kVA b Opt.1

1 44 RO kVA c Opt.1

1 45 RO kVA total Opt1 47 RO Frequency Opt.



3300 ACM DATA REGISTERSFigure G-3c 3300 ACM Data Registers - Part III


MAXIMUM VALUES: PAGE 2

2 0 RW PAGE Register Basic

Maximum Real-Time Values

2 10 RO Van Opt.2 11 RO Vbn Opt.2 12 RO Vcn Opt.2 13 RO Vln average Opt.2 14 RO Vab Opt.2 15 RO Vbc Opt.2 16 RO Vca Opt.2 17 RO Vll average Opt.2 20 RO Ia Opt.2 21 RO Ib Opt.2 22 RO Ic Opt.2 23 RO Iaver Opt.2 30 RO kW a Opt.1

2 31 RO kW b Opt.1

2 32 RO kW c Opt.1

2 33 RO kW total Opt.2 34 RO kVAR a Opt.1

2 35 RO kVAR b Opt.1

2 36 RO kVAR c Opt.1

2 37 RO kVAR total Opt.2 38 RO PF a Opt.1

2 39 RO PF b Opt.1

2 40 RO PF c Opt.1

2 41 RO PF total Opt.2 42 RO kVA a Opt.1

2 43 RO kVA b Opt.1

2 44 RO kVA c Opt.1

2 45 RO kVA total Opt.2 47 RO Frequency Opt.

Notes:1. 1 Available in Wye mode only2. Register Types: RO = Read Only

WO = Write OnlyRW = Read/write


Maximum Thermal Demand Values

2 110 RO Van Dmd Opt.2 111 RO Vbn Dmd Opt.2 112 RO Vcn Dmd Opt.2 113 RO Vln aver Dmd Opt.2 114 RO Vab Dmd Opt.2 115 RO Vbc Dmd Opt.2 116 RO Vca Dmd Opt.2 117 RO Vll aver Dmd Opt.2 120 RO Ia Dmd Opt.2 121 RO Ib Dmd Opt.2 122 RO Ic Dmd Opt.2 123 RO Iaver Dmd Opt.2 130 RO kW a Dmd Opt.1












2 145 RO kVA total Dmd Opt.2 147 RO Frequency Dmd Opt.

Maximum Sliding Window Demand Values




Figure G-3d 3300 ACM Setup Registers - Part IV


SPECIAL PURPOSE REGISTERS: PAGE 10

10 0 WO Page Register Basic10 1 RW PT primary voltage Basic10 2 RW PT secondary voltage Basic10 3 RW CT primary current Basic10 4 RW Voltage input mode

(0,1,2,3 or 4) Basic10 5 RW Unit ID number Basic10 6 RW Baud rate (300,1200,2400,

4800,9600,19200) Basic10 7 RW Demand period

time constant Basic10 8 RW Contrast/viewing

angle adjustment Basic10 9 RW Password Basic10 10 WO Reset all min/max values

(if equipped) Basic10 11 WO Reset all hour counters

(kW hours Etc.) Basic10 12 RO Firmware revision number Basic10 13 RO Date the last firmware

revision was performed Basic10 14 RO Feature code Basic10 15 RO Device type

(will equal 3300) Basic10 16 RW Allow protected reads only

(yes or no) Basic10 17 RW Number of demand periods

(yes or no) Basic

Description of Special Purpose Registers

RESET ALL MIN/MAX VALUESAny write to this register will result in any min/max valuesbeing set to the present real time values.

Any Sliding Window Demand min/max values will be set tozero.

RESET ALL HOURS COUNTERAny write to this register will result in any hour counters (kWhours import, kVAR hours total, Etc.) being set to zero.

FIRMWARE REVISION NUMBER A four digit decimal representation of the firmware revisionnumber. For example a value of 0004D2 hex = 1234 decimalwould represent a hypothetical firmware revision of 1.2.3.4.

FEATURE CODEReserved for future use. Presently this will return zero.

DEVICE TYPEWill return 3300. This will be used in future to differentiatedifferent devices using this same protocol format.

ALLOW PROTECTED READS ONLYBoolean value (0 or 1) that determines whether a password isrequired to read data from the meter. If a 1 is written to thislocation, any read request packet must contain a correctpassword or the packet will be ignored. If a 0 is written, nopassword is required for normal register reads. Zero is thedefault.



Request from Master:14 FD 83 0A 00 00 64 00 00 00 00 00 FF 00 12

Response from 3300ACM:27 FD 83 90 64 00 00 00 E4 0C 22 00 64 00 00 0A64 00 00 0B 64 00 00 0C 64 00 00 0D AD 00 00 0EAD 00 00 0F AD 00 00 10 AD 00 00 11 88 13 00 1488 13 00 15 88 13 00 16 88 13 00 17 F4 01 00 1EF4 01 00 1F F4 01 00 20 DC 05 00 21 00 00 00 2200 00 00 23 00 00 00 24 00 00 00 25 E8 03 00 26E8 03 00 27 E8 03 00 28 E8 03 00 29 F4 01 00 2AF4 01 00 2B F4 01 00 2C DC 05 00 2D AE 0F 00 2FDA 2F 01 36 00 00 00 37 93 0E 00 40 00 00 00 411F 05 00 85 55

Figure G-4 Read Registers Example

Figure G-5 Write Registers Example

5.2 WRITE REGISTERS EXAMPLE

Figure G-5 demonstrates is an example of a register writeto set the voltage scales, current scale and voltage mode ofa meter with unit ID 100 and a password of 0. TheMaster will write the following information to the 3300ACM:

• PT primary voltage 1200

• PT secondary voltage 120

• CT primary current 5000

• Voltage mode 0

Write command from Master:14 FD 81 1C 00 00 64 00 00 00 05 00 0A 00 00 00B0 04 00 01 78 00 00 02 88 13 00 03 00 00 00 0421

Response from 3300ACM:27 FD 81 07 64 00 00 00 E4 0C FF 27

5 PACKET EXAMPLESThe following two sections contain examples of actual packetssent to a 3300 ACM meter, and the response packets issuedby that meter. To make the packets easier to read the byteshave been blocked into groups of 4.

5.1 READ REGISTERS EXAMPLE

Below is an example of a request from a Master Station to unit100. The request is for all registers in the range 0000 to 00FFhex, which is a request for all real-time and demand param-eters. The Master Station has ID number 0.

Documents

3300 ACM Installation & Operation Manual - apc.com · 3300 ACM Installation and Operation Manual Power Measurement Ltd. iv Table of Contents 3.5 Selecting Direct or PT Input & Setting