0990_ Manual Servicio Monorail Overhead

0990 Monorail Overhead Track Scale Installation and Service Manual

A14859600A (9/04).00

Mettler-Toledo, Inc. 1996, 2004

No part of this manual may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, for any purpose without the express written permission of Mettler-Toledo, Inc.

U.S. Government Restricted Rights: This documentation is furnished with Restricted Rights.

METTLER TOLEDO

Publication Revision History An overview of this manuals revision history is compiled below.

Publication Name: 0990 Monorail Overhead Track Scale Installation and Service Manual Publication Part Number: 14859600A Publication Date: 6/96

Part Number Date Revisions A14859600A 9/04 Revised and reformatted manual.

INTRODUCTION This publication is provided solely as a guide for individuals who have received Technical Training in servicing the METTLER TOLEDO product.

Information about METTLER TOLEDO Technical Training can be obtained by writing, calling, or faxing:

METTLER TOLEDO 1900 Polaris Parkway Columbus, Ohio 43240 USA Phone: (614) 438-4511 Fax: (614) 438-4958 www.mt.com

FCC Notice

This device complies with Part 15 of the FCC Rules and the Radio Interference Requirements of the Canadian Department of Communications. Operation is subject to the following conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his own expense.

METTLER TOLEDO RESERVES THE RIGHT TO MAKE REFINEMENTS OR CHANGES WITHOUT NOTICE.

PROPRIETARY NOTICE The information contained in this publication is derived in part from proprietary and patented data of METTLER TOLEDO. This publication shall not be copied in whole or in part without prior written approval of METTLER TOLEDO, nor shall it be used for any purpose other than that intended. This document is subject to change without notice.

STANDARD WARRANTY METTLER TOLEDO warrants that the equipment covered by this warranty will be free from defects in workmanship and material for one year from date of installation or eighteen (18) months from date of shipment to the buyer, whichever comes first.

Should any such defects be found and reported during the first thirty (30) days after installation (if installation occurs during the warranty period), METTLER TOLEDO (herein referred to as the Company) will, at its option, refund the purchase price or correct such defects, furnishing replacement parts and service free of charge to the buyer. For the remainder of the first 12 months of the warranty term, the Company will furnish necessary replacement parts and on-site technicians service free of charge, provided the Buyer agrees to pay reasonable technicians travel time, vehicle mileage, and associated travel expenses to and from the nearest authorized Company service location. If the equipment is covered by a two-year warranty, for the last 12 months or remaining balance of the warranty period, whichever comes first, the Company will furnish the necessary replacement parts to the Buyer free of charge, provided that the Buyer agrees to pay reasonable technicians on-site labor services, travel time, mileage, and expenses to and from the nearest authorized Company service location. The following are NOT covered under any of these warranties:

1. Initial installation and ongoing scale calibration.

2. Damage to scale components by gross abuse, fire, flooding, explosion, water, voltage surges, or civil disturbance.

3. Normal maintenance or consumable items.

This warranty covers only the Model 0990 monorail overhead track scale. Refer to METTLER TOLEDO Standard Product Warranty for coverage of other scale system components, including scale instrument, printer, and/or other accessories.

THE COMPANY EXPRESSLY WARRANTS THE EQUIPMENT MANUFACTURED BY IT AS SET FORTH HEREIN. THE COMPANY MAKES NO OTHER WARRANTIES EITHER EXPRESSED OR IMPLIED (INCLUDING WITHOUT LIMITATION WARRANTIES AS TO MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE). IN ADDITION, THIS DOCUMENT SHALL CONSTITUTE THE SOLE AND EXCLUSIVE REMEDIES OF THE BUYER FOR ANY BREACH BY THE COMPANY OF ITS WARRANTIES HEREIN.

COMPANY LIABILITY UNDER THIS WARRANTY OR ANOTHER WARRANTY, WHETHER EXPRESSED OR IMPLIED IN LAW OR FACT, SHALL BE LIMITED TO THE REPAIR OR REPLACEMENT OF DEFECTIVE MATERIAL AND WORKMANSHIP, AND IN NO EVENT SHALL IT BE LIABLE FOR CONSEQUENTIAL OR INDIRECT DAMAGES.

This warranty coverage is applicable only to the United States of America.

Export Products: The Company warrants equipment destined for export or sold for export to be free from defects in workmanship and material for a period of one year from date of installation or 18 months from date of shipment to the Buyer, whichever occurs first. Should any such defect be found within that period, parts will be furnished free of charge (ex works) point of origin or final distribution center. If the Buyer requests the performance of warranty work provided for under the foregoing warranty outside of the contiguous United States, the Buyer shall be required to pay for labor, travel time, living, and travel expenses of any personnel required to perform such warranty work.

APPLICATION GUIDES The only warranty of METTLER TOLEDO is for the product it supplies under the Product Warranty Statement listed above. Weighing application guidelines pertain to METTLER TOLEDO products.

Precautions

WARNING PERMIT ONLY QUALIFIED PERSONNEL TO SERVICE THIS EQUIPMENT. EXERCISE CARE WHEN MAKING CHECKS, TESTS, AND ADJUSTMENTS THAT MUST BE MADE WITH POWER ON. FAILING TO OBSERVE THESE PRECAUTIONS CAN RESULT IN BODILY HARM.

CAUTION FOR CONTINUED PROTECTION AGAINST SHOCK HAZARD, CONNECT TO PROPERLY GROUNDED OUTLET ONLY. DO NOT REMOVE THE GROUND PRONG.

WARNING DISCONNECT ALL POWER TO THIS UNIT BEFORE INSTALLING, SERVICING, CLEANING, OR REMOVING THE FUSE. FAILURE TO DO SO COULD RESULT IN BODILY HARM AND/OR PROPERTY DAMAGE.

READ this manual BEFORE operating or servicing this equipment. FOLLOW these instructions carefully. SAVE this manual for future reference. DO NOT allow untrained personnel to operate, clean, inspect, maintain, service, or tamper with this equipment. ALWAYS DISCONNECT this equipment from the power source before cleaning or performing maintenance. CALL METTLER TOLEDO for parts, information, and service. CAUTION

BEFORE CONNECTING OR DISCONNECTING ANY INTERNAL ELECTRONIC COMPONENTS OR INTERCONNECTING WIRING BETWEEN ELECTRONIC EQUIPMENT, ALWAYS REMOVE POWER AND WAIT AT LEAST THIRTY (30) SECONDS. FAILURE TO OBSERVE THESE PRECAUTIONS COULD RESULT IN BODILY HARM OR DAMAGE TO OR DESTRUCTION OF THE EQUIPMENT.

CAUTION OBSERVE PRECAUTIONS FOR HANDLING ELECTROSTATIC SENSITIVE DEVICES.

CONTENTS

1 Introduction.................................................................................................... 1-1 General ..............................................................................................................................1-1 Model Numbers...................................................................................................................1-1 Model/RAM Numbers...........................................................................................................1-2 Load Cells ..........................................................................................................................1-3

Load Cell Specifications .......................................................................................................... 1-3 Approvals ...........................................................................................................................1-3

2 Inspection and Site Selection .......................................................................... 2-1 Inspection...........................................................................................................................2-1 Site Selection .....................................................................................................................2-1

3 Installation..................................................................................................... 3-1 Safety Considerations..........................................................................................................3-1 Assembly and Installation....................................................................................................3-1 Modes of Operation .............................................................................................................3-3

Analog Mode ......................................................................................................................... 3-3 RAAD Mode ........................................................................................................................... 3-4 IDNet Mode ........................................................................................................................... 3-5

Home Run Cable Connection................................................................................................3-6

4 Calibration ..................................................................................................... 4-1 General ..............................................................................................................................4-1 Analog Junction Box............................................................................................................4-1 RAAD Junction Box..............................................................................................................4-2 IDNet Junction Box..............................................................................................................4-2

5 Routine Care and Maintenance........................................................................ 5-1 General ..............................................................................................................................5-1 Site Inspection ....................................................................................................................5-1 Scale Inspection..................................................................................................................5-1

6 Troubleshooting.............................................................................................. 6-1 General ..............................................................................................................................6-1 Isolate the Problem .............................................................................................................6-2 Check Wiring ......................................................................................................................6-2 Check Load Cells ................................................................................................................6-3 Check Mechanical Components............................................................................................6-4 Load Cell Replacement ........................................................................................................6-4

7 Service Parts.................................................................................................. 7-1 0990 Monorail Scale...........................................................................................................7-1

8 Reference Material ......................................................................................... 8-1 Reference Drawings ............................................................................................................8-1 Recommended Spare Parts ..................................................................................................8-1

Chapter 1: Introduction General

1 Introduction

General The Model 0990 monorail overhead track scale is a complete weighing assembly that can be installed as part of a new or existing rail system. It provides accurate weighing in overhead rail systems used in meat processing operations.

The 0990 monorail is available in 1,250-lb and 2,500-lb capacities. Each can be constructed of carbon steel or stainless steel with two live rail lengths (2 feet and 4 feet). The live rail is the weighing portion of the rail assembly, the portion on which the trolley wheel rolls. The assembly also includes a backing bar to support the live rail and suspension components to transfer the load to the load cells. A monorail scale can be loaded up to 100% of its rated capacity anywhere along the length of the live rail.

Model Numbers The following table shows how standard model numbers are determined for currently available 0990 monorail scales.

XXXX X X X X X XX

Model Rail Length Load Cell Material Junction Box Load Cell Type

Load Cell Cable Length

Load Cell Capacity

0990 0 = 24 inches

1 = 48 inches

0 = Carbon steel

1 = Stainless steel

0 = None

1 = Standard analog

3 = IDNet

4 = Large analog

6 = Large IDNet

0 = TLC H44

1 = THC H44

2 = Future

3 = Future

0 = 15 feet

1 = 30 feet

01 = Future

02 = 1,250 lb

03 = 2,500 lb

11 = Future

12 = Future

13 = Future

(9/04) 1-1

METTLER TOLEDO 0990 Monorail Overhead Track Scale Installation and Service Manual

Model/RAM Numbers

RAM Number Description Capacity Shipping Weight

09900011102 Monorail / 2 feet / CS / Analog / H44 THC / 30 feet / 1,250 lb 1,250 lb 170 lb




09900001102 Monorail / 2 feet / CS / No J-Box / H44 THC / 30 feet / 1,250 lb 1,250 lb 167 lb




09900111102 Monorail / 2 feet / SS / Analog / H44 THC / 30 feet / 1,250 lb 1,250 lb 170 lb




09900101102 Monorail / 2 feet / SS / No J-Box / H44 THC / 30 feet / 1,250 lb 1,250 lb 167 lb




(9/04) 1-2

Chapter 1: Introduction Load Cells

Load Cells Model 0990 monorail scales include stainless steel, cantilever-beam load cells with integral, four-conductor, shielded cables. Individual load cell capacities are listed below:

Scale Capacity Capacity of Each Load Cell

Minimum Approved Graduation Size

1,250 lb 2,500 lb

1,250 lb 2,500 lb

0.5 lb 1.0 lb

Load Cell Specifications

Model Number 757

Rated Capacity (RC) 1,250 lb, 2,500 lb

Rated Output 2 mV/V

Maximum Excitation Voltage* 15 VDC or VAC rms

Recommended Excitation Voltage 15 VDC

Input Terminal Resistance 350 ohms minimum

Output Terminal Resistance 350 2 ohms Temperature Range (compensated) +14F to +104F (-10C to +40C)

Safe Overload 150% RC

Safe Side Load 100% RC

Zero Balance 1.0% RC

*The power supply to the load cells is provided by the METTLER TOLEDO indicator.

Approvals NTEP Certification

Model 757 load cells meet or exceed NIST Handbook-44 requirements for Class III 5,000 divisions (multiple cell). A Certificate of Conformance was issued under the National Type Evaluation Program (NTEP) of the National Conference of Weights and Measures (certificate number 96-006).

(9/04) 1-3

Chapter 2: Inspection and Site Selection Inspection

2 Inspection and Site Selection

Inspection When the 0990 monorail scale is delivered, visually inspect it for any damage that might have occurred during shipping and handling. Inspect the following:

1. Scale support frame (check for warping)

2. Load cell and suspension components

3. Load cell cables

4. Load cell summing junction box

5. Live rail and approach rails

If you find any damage, contact your freight carrier immediately.

Site Selection Many problems associated with monorail scale installations are caused by improper site conditions. Before installing the scale, check the proposed location for the following conditions:

1. The section of rail in which the scale will be installed should be straight and level enough to maintain good weighing.

2. The rail at each end of the scale assembly should be capable of supporting the entire weighing capacity of the scale.

3. There should be easy access to the scale for maintenance.

4. There should be no heavy vibrations or wind currents at or near the scale.

5. The scale should not be subjected to excessive or unusual loading due to the location or type of equipment used.

If the site is acceptable, proceed with the installation. If not, choose a new location or select another scale.

(9/04) 2-1

Chapter 3: Installation Safety Considerations

3 Installation

Safety Considerations All welding should be performed by a certified welder per American Welding Society

(AWS) guidelines.

A safety support system (safety chain or wire rope) with a capacity greater than or equal to the scale capacity is required.

WARNING FAILURE TO INSTALL AND USE A SECONDARY SAFETY SUPPORT SYSTEM COULD RESULT IN BODILY HARM OR PROPERTY DAMAGE.

Never place a load on the monorail scale that exceeds the scales rated capacity.

Assembly and Installation

The 0990 monorail scale is shipped as a kit of parts. Figure 3-1 shows a monorail scale with a 2-foot live rail. To assemble the scale, refer to the assembly drawing for your specific scale and use the following procedure:

1. Attach the backing bar to the live rail, using 1/2-13 UNC flat-head socket screws. Torque the screws to 60 ft-lb.

2. Attach the approach rail support blocks to the base weldment, using 1/2-13 UNC socket-head cap screws. Torque the screws to 100 ft-lb for carbon steel scales or 75 ft-lb for stainless steel scales.

3. Attach the approach rails to the support blocks, using 1/2-13 UNC flat-head socket screws. Do not tighten the screws at this time.

4. Mount the load cells to the base weldment, using 1/2-13 UNC socket-head cap screws. Torque the screws to 100 ft-lb for carbon steel scales or 75 ft-lb for stainless steel scales.

WARNING FAILURE TO TORQUE MOUNTING SCREWS TO THE CORRECT SPECIFICATIONS COULD RESULT IN BODILY HARM OR PROPERTY DAMAGE.

(9/04) 3-1


NOTE: Sleeve bearings fit snugly into the live rail bore. Take care to insert them squarely into the rail. NOTE: The approach rails are replaceable parts. Welding rails to the building superstructure or adjacent rails will complicate future replacement.

5. Attach the live rail assembly to the load cells, using the load support pins and hardware. Make sure that there is 1/16 inch of clearance between the live rail and the approach rails (see Figure 3-2). Torque the load support pins to 200 ft-lb.

6. Tighten the approach rail screws to 60 ft-lb.

7. Align the approach rails with the existing monorail.

8. When the rails are aligned and level, attach the 0990 monorail scale assembly to a nearby superstructure using appropriately sized mounting struts.

Support Block

Load Cell 1

Approach Rail Base Weldment Load Cell 2

Backing Bar

Figure 3-1: Monorail Scale Assembly (with 2-Foot Live Rail)

Figure 3-2: Clearance Between Live Rail and Approach Rails

Support Block

Load Support Pin

Load Support Pin

Live Rail

Approach Rail

1/16" 1/16"

Approach Rail Approach RailLive Rail

(9/04) 3-2

Chapter 3: Installation Modes of Operation

Modes of Operation

Analog Mode A Model 0990 monorail scale can be used with an analog junction box for summing the load cell outputs. An analog junction box must be used with a compatible analog indicator. See Figure 3-3 and Table 3-1 for the correct cable connections. Load cells are numbered as indicated in Figure 3-1.

NOTE: Use 24-gauge instrument cable (P/N 510624370) for 50 feet or less. Use 20-gauge instrument cable (P/N 510620370) for distances longer than 50 feet.

Figure 3-3: Analog Junction Box Detail

Load Cell Wiring Instrument Cable Wiring*

Function Color Function Color

+Excitation Green +Excitation White

+Sense Not Used +Sense Yellow

+Signal White +Signal Green

Shield Yellow Shield Orange

-Signal Red -Signal Black

-Sense Not Used -Sense Red

-Excitation Black -Excitation Blue

*Instrument cable color code based on METTLER TOLEDO cable number 510624370

Table 3-1: Analog Junction Box Wiring Codes

AUX

INPU

T

+EX

E +

SIG

SH

LD

-SIG

-E

XE

+EX

E +

SIG

SH

LD

-SIG

-E

XE

+EX

E +

SIG

SH

LD

-SIG

-E

XE

+EX

E +

SIG

SH

LD

-SIG

-E

XE

LC2

LC1

LC4

LC3

ANALOG JBOX A/N 13640300A

+EXE +SEN +SIG SHLD -SIG -SEN

+EXE +SEN +SIG SHLD -SIG -SEN

Individual Load Cell Trimming Potentiometer

NOTE: Turn all potentiometers fully clockwise prior to calibration.

To LC2

To Indicator

To LC1

NOTE: Do not cut load cell cables. Cutting a cable will affect compensation and void the warranty.

(9/04) 3-3


RAAD Mode A Model 0990 monorail scale can be used with a RAAD junction box for summing load cell outputs. A JAGUAR or JAGXTREME indicator must be used with the RAAD junction box. The indicator serves as the host for the RAAD junction box, allowing you to use the indicators keypad to adjust scale parameters. See Figure 3-4 and Table 3-2 for cable connections. Load cell wiring for RAAD mode is the same as for analog mode. Load cells are numbered as indicated in Figure 3-1.

WARNING! DO NOT USE THE RAAD JUNCTION BOX IN LOCATIONS CLASSIFIED AS HAZARDOUS BY THE NATIONAL ELECTRICAL CODE (NEC) ARTICLE 500.

W1

TB1 TB2

#1

+VB+VA

NOTE: A DigiTOL POWERCELL card must be installed in the JAGUAR or JAGXTREME indicator.

NOTE: If more than one junction box is used, connect the junction boxes in a daisy chain. Connect Terminal TB5 on the first junction box to Terminal TB2 on the next junction box in the series.

The addresses of the DigiTOL cards in the second RAAD box must be reset to the factory settings and then re-addressed to the correct load cell number.

Switch Positions (SW) SW1: On if Load Cell 1 is used SW2: On if Load Cell 2 is used SW3: On if Load Cell 3 is used SW4: On if Load Cell 4 is used SW5: On if last J-box in series

To Jaguar To Cell 1

NOTE: For 2 mV/V load cells, jumpers W1, W2, W3, and W4 must be ON (shorting the pins).

COM

A

COM

B

GN

D

GN

D

GN

D

+VC

+

VB

+VA

-EXC

-S

IG

SHLD

+

SIG

+

EXC

Figur

RAAD TB2 Terminal

1

2

3

4

5

6

7

8

Tabl

(9/04) 3-4 ON 1 2 3 4

W2

TB3

SW

#2

To Cell 2

-EXC

-S

IG

SHLD

+

SIG

+

EXC

e 3-4: RAAD Jun

Fun

+20 VD

+20 VD

+20 VD

Gro

Gro

Gro

CO

CO

e 3-2: RAAD Junc 5

W3

TB4 TB5

#3 #

+VA +VC

To 2nd J-BoxTo Cell 3

COM

A

COM

B

GN

D

GN

D

GN

D

+VC

+

VB

+VA

-EXC

-S

IG

SHLD

+

SIG

+

EXC

ction Box Detail

ction Jaguar T

C (+VA) 8

C (+VB) 7

C (+VC) 6

und 5

und 4

und 3

M B 2

M A 1

tion Box Wiring 4W4

T

To C

-EXC

-S

IG

ermin

B6

ell 4

SHLD

+

SIG

+

EXC

al

Chapter 3: Installation Modes of Operation

IDNet Mode The IDNet junction box can output an IDNet data format compatible with METTLER TOLEDO IDNet weight displays. See Figure 3-5 and Table 3-3 for cable connections. For detailed information about the indicator capabilities and operating instructions, refer to the appropriate service manual. Load cells are numbered as indicated in Figure 3-1.

WARNING! DO NOT USE THE IDNet JUNCTION BOX IN LOCATIONS CLASSIFIED AS HAZARDOUS BY THE NATIONAL ELECTRICAL CODE (NEC) ARTICLE 500.

C

ST2 ST3

P P8 7

P1 P2SA1

87654321

1 2 3 4 5

7

-SIG

+SI

G

8 9

-EXC

+

EXC

-SEN

+SE

N

W3

LC1 LC2

LC4 LC3 6

W2 W5

W1

Figure 3-5: IDNet Junction Box Det

Terminal ell + Exc.

Green - Exc. Black

+ Sig. White

- Sig. Red

#1 4 4 9 9 #2 3 3 8 8 #3 2 2 7 7 #4 1 1 6 6

ail and Wiring

(9/04) 3-5


Jumper Status Description

W1 Closed (ON) Matching the gain at 2 mV/V load cells

W2 Closed (ON) No external sensing (-SEN)

W3 Closed (ON) No external sensing (+SEN)

W4 Closed (ON) Internal reference voltage = 3.5 Volts

W5 Open (OFF) Excitation voltage for load cells = 4.0 Volts

W6 Closed (ON) Internal supply voltage = 7.1 Volts

W7 2-3 Protocol IDNet

W8 1-2 Interface 20 mA

W9 Open (OFF) Supply voltage IDNet

SA1 Closed (ON) Trim potentiometers circuit disabled

NOTE: For 2 mV/V load cells, jumpers W1, W2, W3, and W4 must be ON (shorting the pins).

Table 3-3: IDNet Default Factory Settings

Home Run Cable Connection

Cord Grip Cap

Nut

Spherical WasherJunction BoxEnclosureHome Run Cable

Rubber Grommet

Body Insert

Figure 3-6: Cord Connection Details

Connect the home run cable from the scale indicator to the junction box (refer to Figure 3-6):

1. Wire the home run cable to the PCB according to Figure 3-3 for Analog, Figure 3-4 for RAAD, or Figure 3-5 for IDNet.

2. Place the desiccant bag inside the junction box.

3. Reinstall the junction box lid. Make sure that the rubber gasket is clean and correctly positioned. Tighten all screws and make sure all cord grip caps are secure.

(9/04) 3-6

Chapter 4: Calibration General

4 Calibration

General


Calibrate the scale according to the procedure described in the manual for the scale indicator. The scale should be calibrated using certified test weights that can be traced to the National Institute of Standards and Technology (NIST).

Analog Junction Box Hang the test weight from the scale, using the type of hanger/trolley that will be used to convey product across the scale. The test weight should equal or exceed the largest load that will be weighed on the scale (minimum of 50% of scale capacity).

1. Remove the cover from the junction box and turn the load cell trim potentiometers fully clockwise.

2. Apply power to the indicator and calibrate the scale.

3. Span the scale by placing the weight in the center of the live rail.

4. After initial calibration is complete, place the test weight alternately at each end of the live rail. Record the weight reading at each position.

5. Place the weight at the end of the live rail at which the highest weight reading was recorded. Turn the corresponding trim potentiometer counterclockwise until the reading agrees with the reading recorded at the other end of the live rail.

6. Repeat Steps 4 and 5 until the readings at both ends of the live rail are equal.

7. Recheck the calibration. If the span is off, adjust the span using the procedure described in the indicator manual.

8. Place a desiccant bag inside the junction box and reinstall the cover.

(9/04) 4-1


RAAD Junction Box Perform the shift adjust procedure at the indicator, with the indicator in Setup mode. For shift adjustment instructions, refer to the indicator manual.

IDNet Junction Box Perform the shift adjust procedure using the load cell trim potentiometers mounted on the PCB inside the IDNet junction box (see Figure 4-1).

-SIG

+SI

G

1 2 3 4 5

7

8

9

-EXC

+

EXC

-SEN

+SE

N

W3

LC1 LC2

LC4 LC3

ST2 ST3

P7 P8

P1 P2SA1

87654321

6

W2 W5

W1

LC4

LC3

LC2

LC1

Potentiometer Pair LC1




Hook Switches

Figure 4-1: IDNet Potentiometer Adjustment 1. Place the test weight alternately at each end of the live rail. Record the weight

reading at each position. If the readings are within the desired tolerance, no shift adjustment is needed. Otherwise, perform Steps 2 to 4.

2. Activate the trim potentiometers by opening the eight hook switches (if they are not already open) on the PCB (see Figure 4-1). Once activated, the switches remain open. Do not close the switches, even after completing the shift adjustment.

3. Place the test weight at the end of the live rail at which the highest weight reading was recorded. Turn the corresponding trim potentiometers (each load cell has two) counterclockwise to decrease the reading (clockwise increases the reading).

4. Check the weight readings again, with the test weight positioned at each end of the live rail. Repeat Step 3 until the readings at both locations are the same or within the specified scale tolerances.

5. Make sure all cable connectors and cord grip caps are tight. Then place a desiccant bag in the box, leave all hook switches open, and reinstall the junction box lid.

(9/04) 4-2

Chapter 5: Routine Care and Maintenance General

5 Routine Care and Maintenance

General Once the scale has been installed, have an authorized METTLER TOLEDO representative inspect and calibrate it periodically. If the scale is used for legal-for-trade purposes, consult the local weights and measures authorities for minimum inspection requirements. Contact your local authorized METTLER TOLEDO service representative for information about periodic inspection and calibration services.

Site Inspection Make sure that the scale site remains in good condition. Check for alterations in the surrounding rail support, excessive vibrations, and possible overloading conditions.

Scale Inspection During periodic inspections of the scale, check the following:

1. Are there any unusual wear points, paths, or marks on the live or approach rails?

2. Is the monorail scale attached securely to the superstructure?

3. Is the junction box lid properly sealed and are all cable connectors tight?

4. Is there any moisture or foreign material around or inside the junction box?

5. Is the instrument cable damaged or binding the scale?

6. Is there any debris or material build-up under or around the live rail that could prevent it from moving freely?

7. Are all screws and load support pins torqued according to the specifications in Chapter 3?


8. Are there signs of unusual wear on the load cells, live and approach rails, or suspension components (bearing rings, etc.)?

9. Check repeatability and shift of the scale.

(9/04) 5-1

Chapter 6: Troubleshooting General

6 Troubleshooting

General If the scale does not operate properly, find out as much about the problem as possible. Try to determine whether the problem is constant or intermittent. Mechanical and electrical influences can cause malfunctions, so be patient and use sound logic when troubleshooting.

When troubleshooting a Model 0990 monorail scale, examine the scales physical location. Check for the presence of water, corrosive materials, binding at the live rail, high vibrations, air currents, or physical damage to the live rail or approach rails. Also check the instrument cable for damage, and check all connections for loose or improper wiring.


CAUTION BEFORE CONNECTING/DISCONNECTING ANY INTERNAL ELECTRONIC COMPONENTS OR INTERCONNECTING WIRING BETWEEN ELECTRONIC EQUIPMENT, ALWAYS REMOVE POWER AND WAIT AT LEAST THIRTY (30) SECONDS. FAILURE TO OBSERVE THESE PRECAUTIONS COULD RESULT IN BODILY HARM OR DAMAGE TO OR DESTRUCTION OF THE EQUIPMENT.

(9/04) 6-1


Isolate the Problem Determine whether the problem is in the scale or the indicator.

1. Remove power from the system, and then disconnect the indicator from the scale.

2. Connect the indicator to a load cell simulator (analog simulator available from METTLER TOLEDO).

3. Reapply power and test the indicator. If the problem persists, consult the indicator manual for further troubleshooting assistance.

4. If the problem is NOT present with the load cell simulator attached to the indicator, remove power, disconnect the simulator, and reconnect the scale. If the problem persists, continue troubleshooting the scale.

Check Wiring 1. Remove power from the system.

2. Remove the lid from the junction box and check the interior for moisture and foreign material.

3. Make sure that all wiring connections are tight and that no insulation material is touching the terminal contacts.

4. Check all cable connections to make sure they are wired correctly. The wiring color codes are given in Table 6-1:

Load Cell Wiring Instrument Cable Wiring*

Function Color Function Color

+Excitation Green +Excitation White

+Sense Not Used +Sense Yellow

+Signal White +Signal Green

Shield Yellow Shield Orange

-Signal Red -Signal Black

-Sense Not Used -Sense Red

-Excitation Black -Excitation Blue

*Instrument cable color code based on METTLER TOLEDO cable no. 510624370

Table 6-1: Load Cell Wiring Color Codes

5. Check all cable connectors and cord grip caps on the junction box.

6. Tighten any loose connectors.

(9/04) 6-2

Chapter 6: Troubleshooting Check Load Cells

Check Load Cells 1. Remove power from the system. Fully disconnect each load cell and check for

proper input/output resistances (see Table 6-2).

Measuring Points Resistance

Any lead to shield or ground Infinity

+Exc (Green) to -Exc (Black) 350 ohms minimum

+Sig (White) to -Sig (Red) 348 to 352 ohms

Table 6-2: Load Cell Measuring Points

2. If resistance is within specification, perform a shorted-signal symmetry test.

Short the signal leads together and place one multimeter lead on the shorted signals and one lead on the +Excitation wire. Note the resistance value.

Remove the lead from the +Excitation wire and place it on the -Excitation wire. The two resistance values should be approximately equal. 3. If the load cells pass the shorted-signal test, reconnect them and reapply power to the scale. Confirm that the proper excitation voltage is reaching the load cells by placing multimeter leads on the excitation positions of each load cell terminal.

4. If proper excitation voltage is reaching the load cells, check the output signal from each cell by disconnecting the signal leads and measuring voltage output. If one cell has a particularly high or low dead-load output, it is suspect. The maximum output possible from any cell is 30 mV at 15 VDC excitation and loaded to gross capacity.

5. If any load cell has an unusual signal, remove all load from that cell by raising the platform.

With the power on, measure the output from the suspect load cell. The no-load zero output should be 1.0% of the full scale output. For example, if the excitation voltage is 15 VDC, then the full scale output would be 30 mV and the no-load zero output should be within 0.3 mV.

NOTE: Remove signal leads from terminals to measure output.

6. If a load cell fails any of the above tests, replace it.

(9/04) 6-3


Check Mechanical Components

Because the design of the 0990 monorail scale is so simple, there are only a few mechanical components to troubleshoot. Make sure that the live rail can move freely and is not touching the approach rails. If the live rail is touching the approach rails, check the following:

1. Check the ends of the live rail and its suspension components for unusual wear. Replace any worn or damaged components.

2. Make sure that the load cells are positioned correctly. If not, loosen the mounting screws, position the load cells correctly, and then tighten the mounting screws.

3. Check the approach rail fasteners for proper torque (see Chapter 3 for torque specifications).

Load Cell Replacement 1. Remove power to the indicator and disconnect the instrument cable.

2. Make sure that the live rail and approach rails are empty.

3. Disconnect the load cell cable from the terminal strip inside the junction box. Loosen the cord grip connector and pull the load cell cable out of the junction box.

4. Remove the load cell mounting screws and the defective load cell.

5. Place the new load cell in position and secure it with the mounting screws. Torque the mounting screws to 100 ft-lb for carbon steel scales or 75 ft-lb for stainless steel scales.

6. Wire the replacement load cell cable to the proper terminal strip in the junction box. Be sure to tighten the cord grip connector around the load cell cable.

7. Attach the live rail to the load cells, using the load support pins and hardware. Make sure that there is 1/16 inch clearance between the live rail and approach rails. Torque the load support pins to 200 ft-lb.

8. Check the calibration and shift adjustment with a certified test weight. Make any adjustments as required.


(9/04) 6-4

Chapter 7: Service Parts 0990 Monorail Scale

7 Service Parts

0990 Monorail Scale Refer to Figure 7-1 and Table 7-1 when ordering parts for a current 0990 monorail scale.

(9/04) 7-1


211

Figure 7-1: 0990 Monorail Scale Assembly

1

13

11

12

45

9 2

3

7

8 7

1115

14

7 61310

(9/04) 7-2

Chapter 7: Service Parts 0990 Monorail Scale

Ref. No. Part Number Description Qty.

1 TB600489-2

TB600490-2

Model 757 Load Cell, 1,250 lb (30-foot cable)

Model 757 Load Cell, 2,500 lb (30-foot cable)

2

2 TN800647

TN800648

1/2-13 Socket Head Cap Screw x 1.75 inches long, Black Oxide

1/2-13 Socket Head Cap Screw x 1.75 inches long, Stainless Steel

12

3 TN400056-10

TN400057-10

Support Block, Carbon Steel

Support Block, Stainless Steel

2

4 TA400048-10

TA400041-10

TA400053-10

TA400058-10

Base Weldment, Carbon Steel (for 2-foot rail)

Base Weldment, Stainless Steel (for 2-foot rail)

Base Weldment, Carbon Steel (for 4-foot rail)

Base Weldment, Stainless Steel (for 4-foot rail)

1

5 TN400046-10

TN400039-10

Departure Rail, Mild Steel (2 feet long)

Departure Rail, Stainless Steel (2 feet long)

1

6 TN400045-10

TN400038-10

Approach Rail, Mild Steel (2 feet long)

Approach Rail, Stainless Steel (2 feet long)

1

7 MZ0901010464 1/2-13 Flat Head Socket Screw x 1 inch (required for 2-foot live rail)

1/2-13 Flat Head Socket Screw x 1 inch (required for 4-foot live rail)

11

15

8 TA400047-10

TA400040-10

TA400055-10

TA400042-10

Live Rail, Mild Steel (2 feet long)

Live Rail, Stainless Steel (2 feet long)

Live Rail, Mild Steel (4 feet long)

Live Rail, Stainless Steel (4 feet long)

1

9 TA400043-10

TA400036-10

TA400054-10

TA400035-10

Backing Bar, Mild Steel (2 feet long)

Backing Bar, Stainless Steel (2 feet long)

Backing Bar, Mild Steel (4 feet long)

Backing Bar, Stainless Steel (4 feet long)

1

10 TN400034 Load Support Pin 2

11 TN400052 Neoprene Spacer 6

12 TN400050 Load Pin Ring Bearing 2

13 TN400049 Sleeve Bearing 2

14 TN400051 Sleeve Bushing 2

15 TN800595 Capacity Label 2

-- TB100391 Analog Junction Box Assembly

Consists of: *13640300A Analog PCB (*May have a letter prefix)

TA800218 Desiccant Bag

1

Table 7-1: 0990 Monorail Scale Assembly

(9/04) 7-3

Chapter 8: Reference Material Reference Drawings

8 Reference Material

Reference Drawings

Scale Material Assembly Drawing

0990 Carbon Steel TB400060

0990 Stainless Steel TB400059

Recommended Spare Parts

For part numbers, refer to the service parts list (Chapter 7).

Quantity Description

1 Load cell (capacity of cell required depends on scale capacity)

1 Junction box circuit board

1 Junction box desiccant bag

(9/04) 8-1

METTLER TOLEDO

Publication Suggestion Report If you have suggestions concerning this publication, please complete this form and fax it to (614) 841-7295

Publication Name: 0990 Monorail Overhead Track Scale Installation and Service Manual Publication Part Number: A14859600A Publication Date: 9/04

PROBLEM(S) TYPE: DESCRIBE PROBLEM(S): INTERNAL USE ONLY Technical Accuracy Text Illustration

Completeness Procedure/step Illustration Definition Information What information is missing? Example Guideline Feature in manual Explanation Other (please explain below) Information not in manual

Clarity What is not clear?

Sequence What is not in the right order?

Other Comments Use another sheet for additional comments.

Your Name: Location:

Phone Number: ( )

Fax this completed form to METTLER TOLEDO at (614) 841-7295

Mettler-Toledo, Inc. Printed in USA 14981600A

METTLER TOLEDO 1900 Polaris Parkway Columbus, Ohio 43240 USA P/N: A14859600A (9/04).00 METTLER TOLEDO is a registered trademark of Mettler-Toledo, Inc. 2004 Mettler-Toledo, Inc. Printed in USA

A14859600A

Chapter 1: IntroductionGeneralModel NumbersModel/RAM NumbersLoad CellsLoad Cell SpecificationsApprovalsChapter 2: Inspection and Site SelectionInspectionSite SelectionChapter 3: InstallationSafety ConsiderationsAssembly and InstallationModes of OperationAnalog ModeRAAD ModeIDNet ModeHome Run Cable ConnectionChapter 4: CalibrationGeneralAnalog Junction BoxRAAD Junction BoxIDNet Junction BoxChapter 5: Routine Care and MaintenanceGeneralSite InspectionScale InspectionChapter 6: TroubleshootingGeneralIsolate the ProblemCheck WiringCheck Load CellsCheck Mechanical ComponentsLoad Cell ReplacementChapter 7: Service Parts0990 Monorail ScaleChapter 8: Reference MaterialReference DrawingsRecommended Spare Parts

Documents

0990_ Manual Servicio Monorail Overhead