Vibration Monitor

Part Number 190127-01 Rev. F (09/07)

Bently Nevada Asset Condition Monitoring

Operation and Maintenance Manual

1900/27 Vibration Monitor

1900/27 Vibration Monitor Operation and Maintenance Manual

ii

Copyright 1994. Bently Nevada LLC.

All rights reserved.

The information contained in this document is subject to change without notice.

The following are trademarks of the legal entities cited:

Sealtite is a registered trademark of Anamet Inc.

Teflon is a registered trademark of DuPont.

iii

Contact Information

The following ways of contacting Bently Nevada are provided for those times when you cannot contact your local representative:

Mailing Address 1631 Bently Parkway South

Minden, Nevada USA 89423

USA

Telephone 1.775.782.3611

1.800.227.5514

Fax 1.775.215.2873

Internet www.ge-energy.com/bently


iv

Additional Information

Notice:

This manual does not contain all the information required to operate and maintain the product. Refer to the following manuals for other required information.

200150, 200155, and 200157 Accelerometers Information and Installation Guide (Part Number 164985-01)

89129 and 190520 Accelerometer User Guide (Part Number 89134-01)

Product Disposal Statement

Customers and third parties, who are not member states of the European Union, who are in control of the product at the end of its life or at the end of its use, are solely responsible for the proper disposal of the product. No person, firm, corporation, association or agency that is in control of product shall dispose of it in a manner that is in violation of any applicable federal, state, local or international law. Bently Nevada LLC is not responsible for the disposal of the product at the end of its life or at the end of its use.

v

Contents

1. 1900/27 Vibration Monitor Description ..................................................... 1

1.1 Features................................................................................................................................................. 1

1.2 Monitor Connections, Indicators, & Controls.......................................................................... 4

2. Installation ...................................................................................................... 6

2.1 Receiving Inspection........................................................................................................................ 6

2.2 Jumper Settings................................................................................................................................. 6

2.2.1 Setting Relays for Latching or Non-Latching Behavior............................................... 7

2.2.2 Setting Relays for Normally Energized or Normally De-energized Behavior .... 7

2.2.3 Setting 4 to 20 mA Interface Behavior During 1900/27 Monitor Bypass............ 8

2.2.4 Internal Jumper Location ......................................................................................................... 9

2.3 Monitor Enclosure.............................................................................................................................. 9

2.4 Configuration Switch Settings ...................................................................................................10

2.4.1 Relay Time Delay ........................................................................................................................10

2.4.2 Alert Relay Alarm Conditions.................................................................................................10

2.4.3 Configuring the Display for English or Metric Units ....................................................11

2.4.4 Initiating Self Test .......................................................................................................................11

2.5 Connecting Remote Reset............................................................................................................12

2.6 4 to 20 mA Interface Connections...........................................................................................12

2.6.1 Connecting Cable to the 1900/27 Monitor 4 to 20 mA Interface .........................12

2.7 Relay Connections ..........................................................................................................................15

2.7.1 Alert Relay Configuration........................................................................................................16

2.7.2 Relay Internal Jumper Settings.............................................................................................17

2.7.3 Relay Electrical Connections..................................................................................................17

2.8 Power Connections ........................................................................................................................19

2.8.1 Types of Power Connections.................................................................................................19

2.8.2 Power Electrical Connections ...............................................................................................19

2.9 Field Wiring Diagram.....................................................................................................................21

3. Monitor Operation....................................................................................... 22

3.1 Monitor Display ................................................................................................................................22

3.1.1 English or Metric Display Units .............................................................................................22

3.1.2 The Display Mode Switch........................................................................................................23

3.1.3 Display Error Codes ...................................................................................................................24

3.2 LED Indicators...................................................................................................................................25

3.3 Relay Mode Switch ..........................................................................................................................26


vi

3.4 Setpoint Adjustment ......................................................................................................................26

3.5 Resetting the Monitor.....................................................................................................................28

3.6 Buffered Transducer Output .......................................................................................................28

3.7 Initiating a Monitor Self Test........................................................................................................28

4. Maintenance & Troubleshooting ...............................................................29

4.1 General Maintenance....................................................................................................................29

4.2 Monitor Adjustments .....................................................................................................................30

4.2.1 LCD Zero Adjustment................................................................................................................30

4.2.2 Adjustment of the Monitor's 4 to 20 mA Current Loop Interface..........................32

4.3 Troubleshooting...............................................................................................................................35

5. Appendix A - Performance Specifications................................................38

5.1 1900/27 Monitor Specification..................................................................................................38

5.1.1 Mechanical Specifications......................................................................................................38

5.1.2 Environmental Specifications ...............................................................................................38

5.1.3 Monitor Power Specifications ...............................................................................................40

5.1.4 Relay Specifications ..................................................................................................................40

5.1.5 Signal Conditioning....................................................................................................................40

5.1.6 Accuracy.........................................................................................................................................41

5.1.7 LED Indicators..............................................................................................................................41

5.1.8 Monitor Controls .........................................................................................................................42

5.1.9 4 to 20 mA Interface Specifications...................................................................................42

6. Appendix B - Peak Detection Methods .....................................................43

6.1 Peak Detector Theory.....................................................................................................................43

7. Appendix C - 1900/27 Monitor Configuration Form ...............................44

8. Appendix D - Accessories and Spare Parts..............................................46

8.1 Installation Hardware ....................................................................................................................46

8.2 Spare Parts.........................................................................................................................................48

9. Appendix E - Hazardous Area Approvals .................................................49

Section 1 - 1900/27 Vibration Monitor Description

1

1. 1900/27 Vibration Monitor Description The 1900/27 Vibration Monitor provides continuous vibration monitoring for machinery where most of the shaft vibration is transmitted through the bearing to the case. Vibration amplitude is a primary indicator of the overall mechanical condition of rotating machinery. Many machine malfunctions, including rotor imbalance, misalignment, and bearing wear can be detected with vibration measurements. Typical applications include general purpose and essential machines with roller element bearings like pumps, fans, and compressors.

This section helps familiarize you with the monitor by listing the features that make the monitor flexible and describing the monitor controls that make the monitor easy to use.

1.1 Features

The features of the 1900/27 Vibration Monitor make the monitor more reliable and easier to use. Many of these features have been used on previous Bently Nevada monitors and have proven to be useful for protecting machinery. You can program some of the features of the monitor by using jumpers or the 6-position Configuration switch.

Some of the non-programmable features are described below.

Transducer separate from monitor - Mounting only the transducer on the machine requires less space and makes the transducer easier to install on small machinery. Mounting the monitor away from the machine protects the monitor from the harsh machine enviroment that is less suitable for electronic instrumentation. This location makes it easier and safer for plant personnel to access the monitor.

Digital LCD display - A digital liquid crystal display on the front of the monitor indicates overall vibration or the Alert or Danger setpoints. Because the monitor is designed to be mounted close to the machine rather than on the machine, the monitor can be located where service personel can read it easily.

Status LED indicators - Four LEDs on the front of the monitor indicate the status of the monitor. These LEDs show whether the monitor is OK, in alarm, or bypassed.

Remote Reset - A front panel reset button and remote reset terminals let you reset latched relays or flashing LEDs without turning the monitor off. The remote reset terminals allows the monitor to be reset from a remote location without having to open the weatherproof enclosure.


2

Relay BYPASS - A relay BYPASS switch lets you disable both relays while you adjust the relay setpoints or maintain the machinery. This feature prevents false alarms or undesired machinery shutdowns. When the monitor is bypassed, the red BYPASS LED is on.

Coaxial connector - A coaxial connector on the front of the monitor provides a buffered velocity signal (500 mV/in/s or 20 mV/mm/s) for locally sampling dynamic data. The connector provides direct access to the integrated transducer signal which can be used to diagnose and analyze machinery.

Two alarm relays - The monitor has two single-pole, double-throw relays (Type 2 FORM C). Use these relays as inputs to the machinery control circuits, or to drive alarm annunciators such as a bell or light on an alarm panel. You can also wire these relays together with other relays into an AND or OR voting logic scheme. Although typically used as an Alert relays, you can reconfigure the Alert relay to become a NOT OK relay, an Alert logically OR'ed with NOT OK relay, or an auxiliary Danger relay. The relay circuits include arc suppressors to increase relay contact life expectancy and reduce arcs in hazardous locations.

4 to 20 mA Intereface - Systems set up to collect data usng a 4 to 20 mA communications system can access the peak velocity data through this interface.

True peak measurements - The 1900/27 Vibration Monitor uses an analog peak-to-peak detector to determine the peak vibration amplitude. This method is more accurate than methods which measure the RMS level and attempt to convert it to peak value. The RMS method is poor because it applies the conversion factor for pure sinusoidal signals even though machinery vibration is rarely a pure sine wave (see Appendix B).

Timed OK/Monitor Defeat - This special proprietary circuit minimizes the possibility of false alarms caused by a defective transducer, transducer wiring, or transducer power supply.

Power-up Inhibit - This feature minimizes false alarms caused by a transient power surge or interruption of power.

Monitor Self Test - The monitor conducts a self test which checks the monitor's power supply voltages and verifies the signal path when you power up the monitor or when you initiate a self test during operation of the monitor.


3

Programmable options provide flexibility and a wide range of standard features.

Internal Jumper Options:

Normally Energized/De-energized Relays - The Alert and Danger relays can be be either normally energized or normally de-energized. The normal condition of a relay corresponds to its non-alarm condition. For example, a normally energized relay would have power on the coil (ARM contacts NO) when it is not in alarm and would remove power from the coil (ARM contacts NC) when it goes into alarm. Both relays are independently set.

Latching/Nonlatching Relays - The Alert and Danger relays can be either latching or nonlatching. Latching alarms must be cleared using the reset button or by closing a switch between the reset terminals. Nonlatching alarms automatically reset when the monitor no longer detects an alarm condition. Both relays are independently set.

4 to 20 mA Interface Behavior during BYPASS - When the monitor is switched to BYPASS, the 4 to 20 mA output sends approximately 2 mA to the host computer. Since some applications require dynamic data collection during BYPASS, you can set the monitor so that it collects data even when the alarms are bypassed.

Front Panel 6-position Configuration Switch Options:

Relay Time Delay - The Alert and Danger relay time delays can be set for 3, 5 , 10, or 15 seconds. Relay time delay is the amount of time that the vibration level must be greater than the alarm setpoint level before an alarm trips. The time delay minimizes false alarms from either "normal" transient vibration or electrical noise sources. The relay time delay setting applies to both relays as long as both are configured to activate under an alarm condition.

Alert Relay Configuration - To help you use the monitor for different applications, the Alert relay can be set to activate under any of the following conditions:

Alert

Alert or NOT OK

NOT OK

Danger (as an auxiliary Danger relay)

Units - You can set the overall vibration level shown on the LCD display to display in either English (in/s) or metric (mm/s) units. Both units are true zero to peak measurements, not RMS measurements converted to peak.

Monitor Self Test - A user-invoked self test switch is provided to aid in field troubleshooting. When you invoke the self test, the signal path and alarm threshold detection circuits are verified. All LEDs and LCD numerical


4

segments turn on at the beginning of the self test to verify that they are operating properly. The power supplies are checked continually.

1.2 Monitor Connections, Indicators, & Controls

The connections, LEDs and LCD, and control switches are shown in the next three figures.

Figure 1-1: Location of monitor connections


5

Figure 1-2: Location of status LED indicators and LCD dsplay location.

Figure 1-3: Location of monitor switches and reset button


6

2. Installation This section describes how to install the 1900/27 Vibration Monitor. It includes information on how to configure the monitor for your particular application using the monitor's internal jumpers and the configuration switches on the front panel. This section also describes how to connect the Accelerometer to the 1900/27 Vibration Monitor.

2.1 Receiving Inspection

Inspect the components of the order as soon as you receive them to see if there was any damage during shipment. Keep all shipping forms and invoices. If any shipping damage is apparent, file a claim with the carrier and submit a copy to Bently Nevada Corporation. Include all model numbers and serial numbers with the claim. We will either repair or replace damaged parts according to the terms and conditions of the sale.

A plastic cover will be over the display when the monitor is shipped from Bently Nevada. Remove the cover from the label either when you receive the monitors or during installation.

2.2 Jumper Settings

Use internal jumpers to program each relay as latching or non-latching and normally energized or de-energized. Use the Bypass Mode jumper to program what 4 to 20 mA interface does during relay bypass.

Section 2 - Installation

7

2.2.1 Setting Relays for Latching or Non-Latching Behavior

A latching relay stays in an alarm state even after the vibration has dropped below the setpoint level for that relay. A non latching relay moves from its alarm state to its non-alarm state once the vibration drops back below the setpoint level for that relay. Table 2.1 describes how to set jumpers W7 and W8 to control latching and non latching behavior for the Alert and Danger relays.

TABLE 2.1: Latching/Non-latching Jumper Settings

OPTION JUMPER SETTING install remove Alert latching* W8 Alert nonlatching W8 Danger latching* W7 Danger nonlatching W7 * Factory default setting

2.2.2 Setting Relays for Normally Energized or Normally De-energized Behavior

The Normally Energized/De-energized option controls whether power is applied to the relay coil during an alarm state or during a non-alarm condition. For normally de-energized relays, no power is applied to the relay coil during non-alarm conditions. Power is applied during alarm conditions. For normally energized relays, power is applied to the relay coil during non-alarm conditions. Power is removed during alarm conditions. Normally energized relays are useful when you want to shut a machine off when vibration monitoring stops due to loss of monitor power. Table 2.2 shows how to set jumpers W5 and W6 for Normally De-energized or Normally Energized Alert and Danger Relays.

TABLE 2.2: Normally Energized and Normally De-energized Jumper Settings

OPTION JUMPER SETTING install remove Alert Normally De-energized* W6 Alert Normally Energized W6 Danger Normally De-energized* W5

Danger Normally Energized W5 * Factory default setting


8

2.2.3 Setting 4 to 20 mA Interface Behavior During 1900/27 Monitor Bypass

With the BYPASS Mode jumper installed the 4 to 20 mA circuit responds to a relay bypass condition at the monitor by sending a NOT OK signal (less than 3 mA) to the plant computer. Even though the relays are in BYPASS, the monitor remains OK and continues to monitor vibration. The 4 to 20 mA circuit is unable to continue sending a vibration signal when this jumper is in, but visibility of a bypass condition is maintained at the plant computer.

With the BYPASS Mode jumper removed, bypassing the relays does not affect the 4 to 20 mA interface.

Table 2.3 shows how to use the Bypass Mode jumper to control how the 4 to 20 mA interface responds when the monitor is bypassed.

TABLE 2.3: Bypass Mode Jumper Settings Response of the 4 to 20 mA interface when

the monitor's relays are bypassed Bypass mode jumper (W4) Flag the point as Not Transmit vibration

OK signal when relays are bypassed

installed* yes no

removed no yes * Factory default setting

To determine realistic setpoint values for a machine, we recommend that you collect data for a few weeks with the relays disabled and the bypass jumper removed. Use this configuration only long enough to collect enough data to determine where to adjust the Alert and Danger setpoints. After you establish realistic setpoints, install the bypass mode jumper and return to the normal monitoring mode by placing the relay mode switch in the NORMAL positrion.


9

2.2.4 Internal Jumper Location

Figure 2.1 shows the location of the jumpers on the monitor's circuit board.

To set the jumpers follow these steps:

1. Remove the case cover: Pull the case cover straight up. The inside of the case cover has a label that summarizes the jumper settings.

2. Locate the five jumpers along the side of the top board (see Figure 2-1).

Figure 2-1: Location of internal jumpers.

3. Remove or insert any of the jumpers that are required for your given application.

4. Snap the case cover back into place over the printed circuit boards.

2.3 Monitor Enclosure

Use a TYPE 4X enclosure for outdoor and Class 1, Division 2 hazardous areas. If the monitor will be in a nonhazardous location where it is protected from the elements, then a weatherproof enclosure is not required. Bently Nevada offers a nonmetallic Type 4X enclosure (Bently Nevada Part Number 190100-01) or a stainless steel RFI resistant Type 4X enclosure (Bently Nevada Part Number 03636315) for 1900 monitors. Both have windows on the front so that the LCD display of the monitor is visible from outside the enclosure. Appendix D provides ordering information. For more information on Bently Nevada's Type 4X enclosures for the 1900 monitor, contact your local Bently Nevada sales representative.


10

2.4 Configuration Switch Settings

Use the 6-position configuration switch on the front panel of the monitor to program the relay time delays, the alert relay alarm condition, English or metric units, and to initiate a monitor self test.

2.4.1 Relay Time Delay

Relay time delay is the amount of time that the vibration must continuously exceed the setpoint before an alarm occurs. Table 2.4 shows the relay time delay switch settings.

TABLE 2.4: Relay Time Delay Settings Switch 1 Switch 2 Time Delay

Off Off 3 seconds

Off On 5 seconds

On Off 10 seconds

On On 15 seconds

2.4.2 Alert Relay Alarm Conditions

Alert relay alarm settings let you configure the Alert relay to be driven by the following 4 conditions: the Alert setpoint, the Alert setpoint logically OR'ed with NOT OK, NOT OK, or the Danger setpoint. If you configure the relay to be driven from NOT OK or the Danger setpoint, the Alert setpoint is no longer used. Table 2.5 shows the Alert relay drive condition settings.

Table 2.5: Alert Relay Alarm Condition Settings

Switch 3 Switch 4 Alert Drive

Off Off ALERT

Off On ALERT OR NOT OK

On Off NOT OK

On On DANGER


11

2.4.3 Configuring the Display for English or Metric Units

English/Metric Units lets you choose which measurement units are used to display the overall vibration level on the LCD as shown in Table 2.6. You may need to re-adjust the zero of the display slightly if you change the units. Refer to section 4.2.1 to calibrate the LCD zero.

Table 2.6: English/Metric Units Settings

Switch 5 Setting Units

Off English Inches/second

On Metric Millimetres/second

2.4.4 Initiating Self Test

Initiate a Self Test by setting switch 6 to the ON position. Return switch 6 to the OFF position once the test has started. The following actions occur during a monitor self test, which lasts approximately 30 seconds:

The relays are placed in their non-alarm states.

Numerical segments of the LCD turn on for the duration of the self test.

All LEDS turn on for the first 4 seconds of the self test.

The signal path circuits are tested

The alarm threshold detection circuitry is tested.

If an error is detected during self test, an error code will remain on at the end of the self test. Error codes E1 and E3 are continually tested for during normal operation. If a power supply failure occurs, E1 comes on. If a NOT OK occurs, the OK LED goes off and E3 comes on. Error code E2, a signal path error, can only be detected using the self test function. The error codes are shown in Table 2.7.

Table 2.7: Self Test Error Codes Code Error Explanation

E1 Power The internal power supply voltages are not within tolerance. E2 Signal Path A fault exists in the vibration signal path, the alert or

danger threshold detection circuits, or the system clock.

E3 NOT OK The transducer, transducer cable, or transducer power supply are not functioning properly.


12

2.5 Connecting Remote Reset

Mounting an external reset switch (or button) at a remote location lets you reset the monitor without having to open the weatherproof housing. The remote reset switch can be mounted up to 305 m (1000 ft) from the monitor. Connect the remote reset switch between the REMOTE RESET A and B contacts. Use a single-pole single-throw (SPST) type switch with normally open contacts which are momentarily closed by the switch actuator.

2.6 4 to 20 mA Interface Connections

Systems set up to collect data using a 4 to 20 mA communication system can access the peak velocity data through this interface. Although the 1900/27 monitor can operate without connecting the 4 to 20 mA interface, the interface lets you collect data automatically for trending.

2.6.1 Connecting Cable to the 1900/27 Monitor 4 to 20 mA Interface

Use two-conductor shielded cable to connect the 4 to 20 mA loop power supply to the 1900/27 Monitor. Cable length is restricted by the loop supply voltage, supply source resistance, and cable impedance. The maximum cable length is determined by:

where L is the maximum cable length in feet, Vs is the minimum loop supply voltage, Vx is any additional voltage drop in the loop, Rs is the supply source resistance, and Zc is the total cable impedance in ohms/ft.

(Note that the above equation accounts for the impedance of both the source and return lines of the cable.)

The following page gives an example for calculating the maximum cable length.


13

Example:

Suppose your 4 to 20 mA system has the following characteristics:

The minimum loop supply voltage is 24 V.

The receiver has a source supply resistance of 250 ohms.

The cable impedance is 12 milliohms/ft.

A device with a constant voltage drop of 1 V is inserted into the loop.

Then the maximum cable length is

Use the following tools to attach the cable to the 1900/27 monitor:

Two-conductor shielded cable.

A screwdriver.

A wire stripper to remove insulation from the cable

Connect the 4 to 20 mA loop to the monitor by following these steps. Refer to Figure 2-10.

1. Strip the outer jacket and the shield foil from the monitor end of the cable.

2. Strip 6.4 to 9.5 mm (0.250 to 0.375 in) of insulation from both of the insulated inner conductors.

3. Use a screwdriver to connect the inner conductors including the shield, or drain, wire to the 4 to 20 mA terminal strip.


14

Figure 2-10: 4 to 20 mA connections


15

2.7 Relay Connections

Alert and Danger relays give two levels of alarm. Use the Alert relay to annunciate high vibration that is nearing the Danger (shutdown) setpoint. Possible annunciators include a buzzer, horn, light, or a signal sent to the plant computer. The Danger relay is dedicated to the Danger setpoint and will go into its alarm state when the vibration level exceeds the Danger setpoint.

WARNING

A missed trip or false trip can occur if the Alert relay is used to signal a shutdown.

Only the Danger relay, because it is dedicated to the Danger setpoint, is intended for machinery protection (shutdown) in the event of high vibration. The Alert relay is intended for non-machinery protection functions, such as annunciating a high vibration condition or a system fault (NOT OK), or for starting a spare machine in the event a primary machine is shutdown by the Danger relay as a result of high vibration in the primary machine.


16

2.7.1 Alert Relay Configuration

The Alert relay can be configured in the field to give an alarm condition from one of four different conditions: Alert setpoint, Alert setpoint logically OR'ed with NOT OK, NOT OK, and the Danger setpoint. Section 2.5.2 shows how to set this relay. Table 2.8 lists the Alert relay configurations and the suggested application for each one.

TABLE 2.8: Suggested Applications for Different Alert Relay Configurations

Alert Relay Driven By

Relay Enters Alarm State When

Suggested Applications

alert setpoint vibration level exceeds the Alert setpoint

Notify that the machine is vibrating at a level approaching the Danger setpoint

Alert setpoint OR'ed with OK relay

vibration level exceeds the Alert setpoint or the monitor is not OK

Notify that the vibration of the machine is high or that a fault exists with the transducer, the transducer wiring, or the transducer power supply

OK relay* the monitor is not OK Notify that a fault exists with the transducer, the transducer wiring, or the transducer power supply

Danger setpoint *

vibration level exceeds the Danger setpoint

Start up a spare machine when the primary machine is shutdown by the Danger Relay

* The Alert setpoint is ignored in these Alert relay configurations; however, the Alert LED will illuminate when the Alert relay is in its alarm state.


17

2.7.2 Relay Internal Jumper Settings

Section 2.2.4 shows how to set the Relay option. Table 2.9 summarizes the effect of the Relay option.

TABLE 2.9: Relay Connections by Normally Energized/De-energized Jumper Settings TERMINAL RELAY OPTION SETTING

(state of the relay with no alarm)

Normally De- Normally Energized energized

4 closed open

5 ARM ARM 6 open closed

7 closed open 8 ARM ARM 9 open closed

If the relay is configured as normally energized then the normally open (NO) and normally closed (NC) connections are reversed from that shown on the label. Use normally energized if you want the relay to change state if the monitor loses power.

2.7.3 Relay Electrical Connections

The following tools and supplies are required for connecting cable to the relay terminal strip:

Wire stripper

Crimp tool

A phillips or straight screwdriver

Crimp type ring or spade lugs

Cable (maximum conductor size: 16 AWG)


18

To install the cable to the terminal strip follow these steps:

1. If an outer jacket is on the relay cable then strip off about 25 mm (1 in) of outer insulation from the cable.

2. Strip 6 mm (0.25 in) of insulation from each of the conductors that will be used by the relay.

3. Crimp a ring or spade lug to each of the conductors using the crimp tool.

4. Open the hinged protective cover over the power and relay terminal strip.

5. Place each lug under the proper screw on the relay terminal strip (see Figure 2-12) and use the screwdriver to tighten the screw.

6. Close the hinged protective cover over the terminal strip.

Figure 2-12: Alert and Danger Relay Connections


19

2.8 Power Connections

The power supply options are 110/220 AC and HVDC, or +24 Vdc. All monitors, regardless of the type of power supply that is chosen, are protected by an internal fuse.

2.8.1 Types of Power Connections

Connect power to the monitor as shown in Table 2.10.

TABLE 2.10: Monitor Power Connections INPUT VOLTAGE CONNECTIONS

85 Vac to 264 Vac 1 2 3

Line Line 2/Neutral Ground

110 Vdc to 370 Vdc 1 2 3

Line 1 Common Ground

24 Vdc 1 2 3

+24 Vdc Common Ground

2.8.2 Power Electrical Connections

Use these tools and supplies to connect cable to the power terminal strip:

Wire stripper

Crimp tool

A phillips or straight screwdriver

Crimp type ring or spade lugs

3 conductor cable (maximum conductor size: 16 AWG)


20

To install the cable to the terminal strip follow these steps:

1. If an outer jacket is on the power cable then strip off about 25 mm (1 in) of outer insulation from the cable.

2. Strip 6 mm (0.25 in) of insulation from each of the conductors that will be connected to the power terminals.

3. Crimp a ring or spade lug to each of the conductors using the crimp tool.

4. Open the hinged protective cover over the power and relay terminal strip.

5. Place each lug under the proper screw on the power terminal strip (see Figure 2-13) and use the screwdriver to tighten the screw.

Figure 2-13: Power Connections 6. Close the hinged protective cover over the terminal strip.


21

2.9 Field Wiring Diagram

A typical field wiring diagram is shown below.

Figure 2-14: Typical 1900/27 field wiring installation.


22

3. Monitor Operation This section describes how to operate the monitor. Included is information about the displays and indicators and how to interpret the information they provide.

3.1 Monitor Display

The liquid crystal display (LCD) on the front panel of the 1900/27 monitor shows vibration data in either English or Metric units. The display can also show the current Alert and Danger setpoint levels and error codes.

3.1.1 English or Metric Display Units

Velocity units can be displayed on the LCD in either English units (in/s), or in Metric units (mm/s). Figure 3-1 shows the arrow on the right side of the LCD that points to the units which the display is currently using. Change the velocity units by setting switch 5 to the desired units on the 6-position configuration switch You may need to re-adjust the zero of the display slightly if you change the units. Refer to section 4.2.1 to calibrate the LCD zero.

Figure 3-1: Location of English and Metric LCD unit indicators.

Section 3 - Monitor Operation

23

3.1.2 The Display Mode Switch

Setpoint levels can be shown on the display by using the three-position Display Mode switch. The positions of the Display Mode switch are Normal, Alert, and Danger. Table 3.1 shows the effects of the Display Mode on the LCD.

Table 3.1: Display Mode Switch

SWITCH SETTING DISPLAY DESCRIPTION

The LCD displays overall vibration in units of in/s.

The LCD displays the Alert Setpoint in units of in/s.

The LCD displays the Danger Setpoint in units of in/s.


24

3.1.3 Display Error Codes

Error codes are displayed on the left side of the LCD as shown in Figure 3-2. If an error is detected the appropriate error code is displayed on the LCD. There are three error codes:

E1 Power supply error (continuously checked)

E2 Signal path error (checked only during self test)

E3 NOT OK error (continuously checked).

The Maintenance and Troubleshooting section, Section 4, contains information about how to resolve these errors.

Figure 3-2: Location of Error Indicators.

Error code E1 indicates a power supply error. The regulated power supplies inside the 1900/27 monitor are continuously checked. If they fall outside of the acceptable power supply range the monitor displays the E1 error code. An E1 error could be caused by a poor power source external to the monitor, or a fault could exist within the monitor itself.


25

Error code E2 is caused by a fault in the signal path. A signal path fault can only be detected during a user initiated self test. If a signal path error is detected during a self test, then an E2 error code will be shown on the LCD display. The signal path check, which is made during self test, verifies that the peak-to-peak detector and the setpoint threshold detectors are working properly. A signal path error could mean that there is an internal fault within the 1900/27 monitor.

Error code E3 occurs when the monitor goes into a NOT OK situation. The monitor continuously verifies that the system is OK. If it detects that a transducer input signal is outside the expected range a NOT OK will result. A NOT OK may be caused by faulty transducer field wiring, a bad transducer, or a bad connection.

3.2 LED Indicators

Four LED indicators on the 1900/27 monitor front panel show the status of the monitor. They indicate whether the monitor and transducer are OK, if either the Alert or Danger relay is in alarm, and whether the relays are bypassed. Table 3.2 summarizes how the LED operate.

Table 3.2: LED Indicators OK LED INDICATION

on Monitor is operating properly and receiving a valid transducer signal

off Monitor is not OK flashing Monitor was not OK and then returned to OK

ALERT LED INDICATION off Alert condition not detected on Alert condition detected. (Section 2.4.2 describes the 4 Alert relay

configurations and explains how to configure the relay.) flashing* Alert condition was detected but is no longer present

DANGER LED INDICATION off The vibration level is less than the Danger setpoint on The vibration level is exceeding the Danger setpoint

flashing* The vibration level has exceeded the Danger setpoint and is now less than the Danger setpoint

BYPASS LED INDICATION off Monitor is operating normally on Monitor is bypassed Monitor is

* Occurs only when the relay is configured as nonlatching and the vibration was previously above the setpoint and has returned below the setpoint for that particular relay.


26

3.3 Relay Mode Switch

The Relay Mode switch lets you inhibit relays by placing the monitor in bypass. The Relay Mode switch has two positions, Normal and Bypass. Table 3.3 describes the behavior of the Relay Mode switch.

Table 3.3: Relay Mode Switch

SWITCH SETTING EFFECT ON RELAYS

Relays react to an alarm condition

Relays do not react to an alarm condition and the Bypass LED comes on. Alert and Danger LEDs continue to track alarm conditions in a nonlatching manner. If relays are activated before the switch is set, they will

3.4 Setpoint Adjustment

Adjust the Alert and Danger setpoints by using the adjustment screws recessed in the front panel of the monitor. The adjustment range for the Alert and Danger setpoints is 2.54 to 50.8 mm/s (0.1 to 1.9 in/s). Use the LCD display to view the setpoint value while adjusting it.

Place the monitor in bypass while adjusting the setpoint so the relays will not activate accidentally. With the monitor placed in bypass, the Alert or Danger LED will come on when the corresponding setpoint is adjusted below the vibration level. If the monitor is taken out of bypass with one or both of these LEDs on, the corresponding relays will activate as soon as the monitor is taken out of bypass.


27

Use a small screwdriver to adjust the setpoints. Figure 3-3 shows the location of the switches and adjustment screws used in this prodedure.

Adjust the setpoints according to the following steps:

1. Place the monitor into Bypass by sliding the Relay Mode switch to the Bypass position with the small screwdriver. The Bypass LED will come on.

2. Slide the Display Mode switch to either the Alert or Danger position, depending on which setpoint you wish to adjust.

Figure 3-3: Location of setpoint adjust screws, Display Mode switch and Relay Mode Switch.

3. Use the small screwdriver to turn the setpoint adjust screw corresponding to the setpoint that you wish to adjust. Turning the screwdriver clockwise increases the setpoint. The value on the LCD changes as the screw is turned. If you adjust the setpoint below the vibration level the LED for the setpoint will come on.

4. When the desired setpoint level is showing on the LCD, verify that the LED for that setpoint is off. If the LED is on when the monitor is taken out of bypass, the relay corresponding to the LED will go into its alarm state.

5. Place the Display Mode switch into the Normal position.

6. Slide the Relay Mode switch into the Normal position by using the small screwdriver.


28

3.5 Resetting the Monitor

Use reset to unlatch a latched relay or to stop a flashing LED. You can reset the monitor by pushing the Reset switch on the front panel or by pressing a remote reset button that is connected to the remote reset terminals.

Remote reset can be accomplished by wiring a normally opened, momentarily closed switch or button to the remote reset terminals. The remote reset contact can be 33 m (1000 ft) from the monitor. The remote reset feature of the 1900/27 lets you reset the monitor without opening the enclosure containing the monitor.

3.6 Buffered Transducer Output

Use the buffered transducer output to obtain the raw integrated transducer signal. The sensitivity of the buffered transducer zero to peak output is 500 mV/mm/s (19.7 mV/in/s).

The buffered transducer output coaxial connector is located on the front panel of the monitor. Use this connector to attach diagnostic equipment such as an oscilloscope or a recorder to the buffered velocity signal.

3.7 Initiating a Monitor Self Test

Self test is initiated by moving switch 6 of the 6-position Configuration switch to the on position. Once the self test begins, move the switch back to the off position. Self test lasts approximately 30 seconds.

When self test begins all the LEDs and numerical segments of the LCD turn on to visually verify that they operate properly. During self test the relays stay in the state they were in at the start of self test. During self test the power supplies are checked, the signal path is verified, and the alarm detection circuitry is tested.

If any part of self test fails, an error code is displayed on the LCD. Error code E1 corresponds to a power supply circuit failure. Error code E2 is a signal path or alarm detection circuit failure. Error code E3 occurs when the monitor is NOT OK. The monitor checks errors E1 and E3 continuously, not just during self test. Error E2, a signal path failure, can only be checked during self test, and will remain on until the monitor is reset even if the failure no longer exists.

Section 4 - Maintenance & Troubleshooting

29

4. Maintenance & Troubleshooting This section describes how to maintain and trouble shoot your 1900/27 monitor. Instructions on how to adjust the LCD's zero potentiometer and the 4 to 20 mA interface's gain adjust potentiometer are included if this procedure should ever become necessary. If you encounter a problem with the 1900/27 monitor, use the troubleshooting table at the end of this section before you contact a Bently nevada Product Service representative.

4.1 General Maintenance

Although the 1900/27 Vibration Monitor is a low maintenance instrument, we recommend that you inspect the monitor every three to six months to verify that the monitor is in good working order and that reliable machinery protection is being provided. Inspect the following items:

The monitor is powered up, the OK LED is on, and the LCD is displaying a valid vibration reading.

The electrical connections to the monitor are in good condition and have no corrosion or loose wires.

The weatherproof enclosure is still properly sealed and does not contain any moisture.

The Alert and Danger setpoints are properly set and the relay time delays and Alert relay drive settings are correct.

During this inspection you should also exercise the self test function of the 1900/27 Vibration Monitor. Note, however, that the 4 to 20 mA interface will not send a vibration signal during self test.


30

4.2 Monitor Adjustments

Two circuits of the 1900/27 monitor may require adjustment. Since these circuits are set at the factory, they should not require adjusting during installation. However, if you suspect that the monitor is out of adjustment, use the following two procedures to adjust these circuits in the monitor.

4.2.1 LCD Zero Adjustment

Use this procedure to adjust the LCD to read zero when no transducer is connected. Because of the noise floor of the transducer, the monitor will display a low value, less than 0.010 in./s (0.254 mm/s), when a transducer is connected and no vibration is present. This adjustment does not affect the full scale range of the monitor.

Adjust the LCD at an electronics workbench rather than at the installation site. A qualified electronics technician or engineer should perform the calibration. If you are not capable of performing this procedure, contact your nearest Bently Nevada sales office and arrange either to send the monitor in for calibration or have Product Service come to your facility and perform this procedure.

Setting the LCD zero requires the following tools and parts:

A small straight blade screwdriver.

A power source for the monitor being calibrated (110 Vac, 220 Vac, or +24 Vdc).

A 3-conductor cable for attaching the power source to the monitor.

Two 3 k resistors.

Several 50 mm (2 inch), 18 AWG wires.


31

The calibration procedure for the LCD is described in the following steps:

1. Remove the case cover by placing pressure with a screwdriver, or similar object, between the case cover and base.

2. Locate the LCD zero adjust potentiometer labeled R20. It is next to the dip switch on the top circuit board.

3. Connect the resistors and 18 AWG wires to the transducer terminal strip according to the circuit shown in Figure 4-1.

Figure 4-1: LCD zero calibration connections.

4. Connect the 3-conductor cable to the monitor power terminal strip and plug the other end of the cable into the proper power source. Wait 30 seconds for the monitor to complete its power up and self test functions. After the power up cycle has finished the green OK LED will flash indicating that the monitor is now completely powered up and OK. To stop the flashing push the reset button.

5. Turn the zero adjust potentiometer until the LCD display reads zero.

6. Unplug the power cable from the power source.

7. Disconnect the power cable from the power supply terminal strip.

8. Disconnect the resistors and jumper wires from the transducer terminal strip.



32

The zero point of the LCD is now properly set. There is no span adjustment for the LCD display. This zero adjust procedure zeros the LCD display for the monitor only. Once a transducer is connected to the monitor, a low value LCD reading, less than 0.250 mm/s (0.010 in/s), will be present when no vibration is present. This reading results from the electrical noise floor of the transducer and monitor system.

4.2.2 Adjustment of the Monitor's 4 to 20 mA Current Loop Interface

Use this procedure to adjust both the zero and the gain of the analog signal from the monitors 4 to 20 mA output to the plant computer. These adjustments should be done by a skilled electronics technician or engineer at an electronics workbench rather than at the installation site. The procedure to adjust this interface requires the following tools and equipment:

A small straight blade screwdriver.

A power source for the monitor being calibrated (110 Vac, 220 Vac, or +24 Vdc).

A 3-conductor cable for attaching the power source to the monitor.

A power source for the 4 to 20 mA interface (+14 Vdc to +30 Vdc, see Appendix A for complete specifications).

A 2-conductor cable for attaching the power source to the 4 to 20 mA interface.

A calibrated multimeter with floating inputs.

A calibrated sinewave generator that can generate-a floating 1.3 Vms sinewave at 614 Hz.. (The output must be floating. Neither one of the two terminals of the sinewave output can be grounded.)

Four 3 k resistors.

Several 50 mm (2 inch), 18 AWG wires.


33

Adjust the 4 to 20 mA interface according to the following steps:

1. Remove the case cover by applying pressure with a screwdriver, or similar object, between the case cover and the base.

2. Locate the 4 to 20 mA zero and gain adjust potentiometers on the bottom circuit board. The potentiometers are labeled R16 and R34 and are located next to the 4 to 20 mA interface connector.

3. Attach the four 3 k resistors, the short lengths of wire, and the sinewave generator as shown in Figure 4-2.

4. Connect the external DC supply to the 4 to 20 mA interface as shown in Figure 4-2.

5. Power up the 4 to 20 mA supply and adjust the voltage to the supply voltage that will be used in the actual installation. If the actual supply voltage is not known, adjust the supply to 22 Vdc.

6. Power the monitor and wait for it to complete self test. After the power up cycle has finished, the green OK LED will flash indicating that the monitor is now completely powered up and OK. Push the reset button to stop the flashing.

Figure 4-2: 4 to 20 mA zero and span adjust circuit.


34

7. With the sinewave generator powered off, measure the DC voltage across the LOOP + and TEST connections on the 4 to 20 mA terminal block. The voltage should be about 0.40 Vdc. If it is not, adjust the zero adjust potentiometer (R16) until the voltage is 0.40 Vdc.

8. Turn the sinewave generator on and adjust the output of the generator for a 1.30 Vrms at 614 Hz. The LCD display should read about 46.7 mm/s (1.840 ips).

9. Measure the RMS voltage on the output on the Buffered Transducer output connector. The multimeter should read 0.65 Vrms. If it does not, adjust the output of the sinewave generator either up or down until the buffered transducer output is 0.65 Vrms.

10. Measure the DC voltage between the LOOP+ and TEST connectors of the 4 to 20 mA terminal block. The reading on the multimeter should be 1.87 Vdc. If it is not, adjust the gain adjust potentiometer up or down until the voltmeter reads 1.87 Vdc.

11. If desired, verify the accuracy of the loop by adjusting the output of the sinewave generator to 0.707 Vrms and measuring the voltage between LOOP+ and TEST. The reading should be between 1.18 Vdc and 1.22 Vdc. If it is not, repeat Steps 7 through 10 of this procedure.

12. Turn off the sinewave generator.

13. Unplug the power cable from both the monitor and 4 to 20 mA power sources.

14. Disconnect the power cable from the power supply terminal strip.

15. Disconnect the resistors, jumper wires and sinewave generator from the transducer terminal strip.



35

4.3 Troubleshooting

Use Table 4.2 to help solve problems encountered while using the 1900/27 Vibration Monitor. If the solutions suggested in this table do not solve your problem, contact your nearest Bently Nevada Product Service Representative.

Table 4.2: Troubleshooting

Problem Possible Solution Monitor will not power up or there is a power supply error code, E1, on the LCD

Verify that input power source is properly connected to the monitor.

Verify that any circuit breakers on the power source are not tripped and that the proper voltage exists on the power input terminals of the monitor.

The monitor has power, but the OK light will not come on.

Check the transducer cable and connectors for opens and shorts.

Replace the transducer with a known good transducer.

The LCD is not reading the proper value

Or

The signal path error, E2 is displayed on the LCD after running a self test on the monitor.

Verify that the Display Mode switch is in the proper position.

Check that the LCD has its zero value properly calibrated. (See Section 4.2.1).

Verify that the transducer is working properly by either replacing it with a known good transducer or by testing the existing transducer for proper operation on a shake table.

Check that the instrument you use to verify the monitor's reading uses the same analog peak to peak divided by 2 measurement that the 1900/27 uses (see Appendix G) .


36

Problem Possible Solution The LCD is blank, except for the leftmost digit isdisplaying a 1.

The input to the LCD circuit is above full scale. Check the input vibration with a portable vibration analyzer, or the buffered transducer output to verify that the vibration is higher than 1.999 in/s.

The relays do not appear to activate when the vibration exceeds the setpoint

Or

The annunciator or machine that the relay is connected to is not affected by an alarm condition at the monitor.

Verify that the setpoints are set properly. Make sure that the monitor is not in Bypass (BYPASS

LED is off) and that the OK LED is illuminated. If the Alert relay is the problem, then verify that the

drive condition for the relay is properly set on the Configration DIP switch.

Test the relay. Before testing either relay disconnect it from any machinery that would be affected by the relay changing state. To test the relay, lower the setpoint below the current vibration level and verify that the relay goes into its alarm state.

Verify that the cable between the monitor's relay terminals and the device the relay is connected to is correct. If the relay is being used to drive an external relay or device, such as a motor control relay or a buzzer, then verify that the external relay or device is working properly.

The 4 to 20 mA interface sends an inaccurate signal or no signal.

Check the 4 to 20 mA interface cable for opens and shorts between the 1900/27 monitor and the plant computer.

Check that the plant computer power supply and loop resistance meet the specifications listed in Appendix A, Section 1.9.

Check calibration of the 4 to 20 mA interface according to the procedures in Section 4.2.2 of this manual.

The 4 to 20 mA interface indicates a NOT OK (output is 1 to 3 mA) but the monitors OK LED is on.

Verify that the bypass mode jumper (W4) is in and that the monitor is bypassed. If these two conditions exist then the monitor is operating correctly. When the W4 jumper is installed the 4 to 20 mA output will indicate a NOT OK when the monitor is bypassed.


37

Problem Possible Solution E3 error is displayed on LCD (NOT OK Condition detected).

Verify that connectors are firmly seated and free of corrosion

Verify transducer is properly wired Verify no shorts exist between wires at connector Verify that the transducer power supply is working

properly by measuring the voltage between transducer PWR(RED)and COM(BLK). Acceptable range is 4.9 to 5.2 Vdc

Verify that the transducer cable is working properly by replacing it with a known good cable

Verify that the transducer is working properly by either replacing it with a known good transducer or by testing the existing transducer for proper operation on a shake table.


38

5. Appendix A - Performance Specifications

5.1 1900/27 Monitor Specification

Note: Operation outside the specified limits will result in false readings or loss of machine monitoring.

5.1.1 Mechanical Specifications

Dimensions (see Figure A-1):

Length: 5.20 in (132 mm)

Width: 5.20 in (132 mm)

Depth: 2.80 in (71.1 mm)

Weight: 0.85 lb (400 g)

5.1.2 Environmental Specifications

Temperature Range:

Operating: -20C to +70C (-4F to 176F)

Storage: -30C to +90C (-22F to 194F)

Maximum Relative Humidity: 95% noncondensing

Section 5 - Appendix A - Performance Specifications

39

Figure A-1: 1900/27 Mechanical Dimensions.


40

5.1.3 Monitor Power Specifications

AC/HDC Version

AC Voltage: 85 Vacrms to 264 Vacrms

DC Voltage: 110 Vdc to 370 Vdc

Current: less than 0.12 Arms Max

Frequency: DC or 47 Hz to 440 Hz

Low DC Version

Voltage: 18 Vdc to 36 Vdc

Current: less than 0.3 A Max

5.1.4 Relay Specifications

Relay Contact Ratings (noninductive load):

Maximum Switched Power: 180 W, 1800 VA

Maximum DC Voltage & Current: 28 Vdc at 6 A

Maximum AC Voltage & Current: 300 Vac at 6 A

Relay Dielectric Strength (at sea level):

Contact to Contact: 750 Vrms

Contact to Coil: 1500 Vrms

Relay Life Expectancy:

Mechanical: 100,000,000 operations

Electrical: 180,000 operations at 6 A, 120 Vac

Insulation Resistance: 100,000,000 Q minimum at 20oC,

500 Vdc, 50% relative humidity

5.1.5 Signal Conditioning

Fullscale Range: 2 in/spk (50.8 mm/spk) Note: Full scale is limited by maximum input above 614 Hz. The Maximum input is 2 volts peak, or 20 g peak. 20 g peak at 614 Hz is equivilant to 2 in/second peak. For frequencies above 614 Hz, the maximum full scale range is equal to (1228/frequency) in/s.

Section 5 - Appendix A - Performance Specifications

41

Frequency Response:

High Pass Corner: 3 dB corner at 8 Hz. Less than 1% error due to high pass corner for frequency above 30 Hz.

Low Pass Corner: Greater than 4 kHz. Less than 1% error due to low pass corner for frequency below 4 kHz.

5.1.6 Accuracy

Percent of full scale range.

Liquid Crystal Display 3% for 30 Hz to 4 kHz

-30%, +3% for 8 to 30 Hz.

Buffered output 3% for 30 Hz to 4 kHz.

-30%, +3% for 8 to 30 Hz.

4 to 20 mA Interface 3% for 30 Hz to 1 kHz.

-30%, +3% for 8 to 30 Hz.

5.1.7 LED Indicators

OK: One constant ON green LED indicates OK condition of monitor, transducer, and field wiring. Constant OFF indicates NOT OK condition. OK LED flashing at 2 Hz indicates monitor has been NOT OK, but is now OK.

Alert: One yellow LED indicates an Alert condition. Flashing at 2 Hz indicates an Alert condition has occurred and then gone away (only occurs if the Alert relay is configured as nonlatching).

Danger: One of the two red LEDs indicates a Danger condition. Flashing at 2 Hz indicates a Danger condition has occurred and then gone away (only occurs if the Danger relay is configured as nonlatching).

Bypass: The other red LED indicates the monitor is in BYPASS mode.


42

5.1.8 Monitor Controls

Display Mode Switch: Three positions: Normal, Alert Setpoint, and Danger Setpoint. Controls what is shown on LCD display.

Relay Mode Switch: Two positions, Normal and BYPASS, control whether the monitor is in normal or Bypass mode.

Reset Button: Push to reset latched relays and flashing LEDs.

Configuration Switch: Used to set Alert and Danger Relay Time Delay, Alert relay drive conditions, English or metric display units, and to initiate a monitor self test.

5.1.9 4 to 20 mA Interface Specifications

Fullscale Range: 2 in/spk (50.8 mm/spk)

Overrange: 2.5 in/spk (63.5 mm/spk)

Frequency Response: 10 Hz to 1 kHz

NOT OK Signalling: Output clamped to less than 3 mA during monitor NOT OK

Input Voltage Range: 12 VDC minimum

36 VDC maximum

Galvanic isolation: Optical, 1000 Vac, 707 Vdc.

Section 6 - Appendix B - Peak Detection Methods

43

6. Appendix B - Peak Detection Methods Understanding the methods for peak to peak amplitude detection of a vibration signal can help you understand why the 1900/27 Vibration Monitor is more accurate than some other monitors and why the readings of the 1900/27 and the Trendmaster 2000 can differ slightly under certain circumstances. This appendix summarizes the typical methods of detecting peak to peak amplitude and then compares the relative value of each one.

6.1 Peak Detector Theory

Three methods of peak detection are commonly used in vibration measurment instruments - the simple peak method, the peak-to-peak divided by 2 method, and RMS converted to peak method. The most accurate method for detecting the peak-to-peak amplitude of vibration signals is the peak-to-peak divided by 2 method.

A simple peak detector circuit will find the maximum positive peak of a waveform. Over some period of time, usually about one second, the peak value held by the circuit decays so the circuit can obtain the next peak value. A peak detection scheme using only a positive peak detector is less accurate because it assumes that the vibration signal has equal positive and negative peaks. When measuring an input vibration signal with a small positive peak and a large negative peak, for example, this detector erroneously indicates a low vibration amplitude. Since complex machine vibration signals are rarely symmetrical, a detector that measures both positive and negative peaks is more accurate.

Peak-to-peak divided by 2 detection is a better method and is used by Bently Nevada monitors for velocity or acceleration signals. This method finds both the positive and negative peaks of the input signal and adds them together to get a peak-to-peak value. Since peak value is the standard for vibration data displayed in velocity units, the monitor divides the peak-to-peak value by two, resulting in the peak value of the signal. The peak values held by this circuit also decay so the circuit can detect future peaks. The peak-to-peak divided by two method ensures that all the vibration signal from a machine, both positive and negative, is measured and the result accurately reflects the overall vibration of the machine.

Another peak detection method is RMS converted to peak, which uses a true RMS detection circuit to find the RMS value of the input signal, then applies a conversion factor to find the peak value. Although some applications may call for RMS measurements, this method is poor for determining true peak values because the relation between RMS and peak values depends on the shape of the signal. Typically, instruments convert RMS to peak by dividing by V2, which is only accurate for a pure, symmetrical sinusoid. Since complex machine vibration signals are rarely pure or symmetrical sine waves, the peak value obtained from this method is usually in error.


44

7. Appendix C - 1900/27 Monitor Configuration Form

The following page contains a form that can be used to record internal jumper settings, configuration switch settings, and setpoints for the 1900/27 monitor.

The configuration form may be copied.

Section 7 - Appendix C - 1900/27 Monitor Configuration Form

45

1900/27 Vibration Monitor Configuration Form Monitor

Configuration:

Point Plant Name : ___________________________________________ Location Unit Name : ___________________________________________

Machine Name : ___________________________________________ Machine Type : ___________________________________________

Transducer Orientation: Radial | Axial Angle: ________________ Orientation Zero Degree Reference: ____________________________

Setpoint Alert Setpoint : ___________ in/s | mm/s Levels Danger Setpoint : ___________ in/s | mm/s

Jumper W4 - Trendmaster 2000 Bypass Mode : IN | OUT Settings W5 - Danger Relay Normally Energized/ De-energized Mode : IN | OUT W6 - Alert Relay Normally Energized/ De-energized Mode : IN | OUT W7 - Danger Relay Latching/Nonlatching Mode : IN | OUT W8 - Alert Relay Latching/Nonlatching Mode : IN | OUT

Configuration Relay Time Delay : 3 s | 5 s | 10 s | 15 s Switch Alert Relay Drive : Alert | Alert OR NOT OK | NOT OK | Danger Settings Velocity Units (peak) : English - in/s | Metric - mm/s

(This page may be copied)


46

8. Appendix D - Accessories and Spare Parts

8.1 Installation Hardware

The following items listed below can be used as part of the installation of the 1900/27 Vibration Monitor.

Weatherproof Enclosure

A weatherproof enclosure protects the 1900/27 Vibration Monitor from wet and corrosive environments. Two enclosures are listed below. When properly installed, these weatherproof enclosures will meet Type 4X specifications.

Constructed of thermoplastic polyester resin (PBT), the 190100-01 weatherproof enclosure has a clear polycarbonate cover to allow viewing of the LCD display and status LEDs.

When properly installed, the 03636315 RFI Resistant Enclosure protects the 1900/27 monitor from strong radio signals generated from hand-held transmitters. It consists of a stainless steel body and a door with a metal screened window. Along with the 190520 Accelerometer and properly grounded conduit, this housing can significantly reduce the possibility of nuisance alarms caused by radio induced signals.

190100-01 Weatherproof enclosure for one 1900/27 Vibration Monitor.

03636315 Weatherproof RFI shielded enclosure for one 1900/27 Vibration Monitor.

104795-01 Back panel for 03636315 housing.

04344054 Screws for 03636315 housing back panel.

Section 8 - Appendix D - Accessories and Spare Parts

47

Fittings

03813103 3/4 inch NPT chrome plated zinc hub fitting.

03813106 1-1/4 inch NPT chrome plated zinc hub fitting.

26650-01 3/4 inch to 1/2 inch NPT reducer.

26650-03 1-1/4 inch to 1 inch NPT reducer.

03839240 1/4 inch NPT cable seal; 0.200 to 0.265 inch diameter (5.0 to 6.7 mm) for use in sealing transducer cable entry to weatherproof enclosure. One required per each cable entry to housing.

03870190 fitting for connecting 1/2 inch NPS female liquidtight conduit to 1/2-14 NPS transducer cap option.

Cable Armor and Fittings

Cable armor can be used to make the transition from the transducer to Sealtite flexible conduit or rigid conduit.

Armor

106924 AXX 3/8 inch Teflon coated stainless steel armor

Option Decription

A: Armor length option in feet

Order in increments of 10 feet (3.0 metres).

Minimum length: 3.0 metres (10 feet)

Maximum length: 27 metres (90 feet)

Armor Fittings

03840496 Armor to 1/2 inch NPS female conduit fitting for connection to 1/2 inch NPS transducer cap option.

03840495 Armor to 3/4 inch conduit fitting


48

8.2 Spare Parts

An on-site supply of spare parts allows for immediate and efficient maintenance or expansion of your 1900/27 Vibration Monitor System. Bently Nevada recommends that the following components be available as spare parts.

Cable connector plugs

A 7 position connection plug is required for connecting the transducer and 4 to 20 mA system cables to the 1900/27 Vibration Monitor.

00500133 7 position 5.08 mm spacing connector plug

Jumpers

The internal jumpers are used to set relay options such as latching or nonlatching relays and normally energized or de-energized relays.

00500143 single 2 pin jumper

Manual

Spare manuals may be useful to allow other engineers or technicians, involved in the installation, operation, or maintenance of the 1900/27 Vibration Monitor, to have their own copy.

190127-01 1900/27 Operation and Maintenance Manual

Section 9 - Appendix E - Hazardous Area Approvals

49

9. Appendix E - Hazardous Area Approvals

Canadian Standards Association Approvals

The 1900/27 vibration monitor is CSA NRTL/C approved for Class 1, Division 2, Groups A,B,C,D hazardous areas when installed per drawing 105352.

The table below lists the approval drawings in the order they appear.

APPLICATION NOTE

When the accelerometer is used with barriers in an intrinsically safe installation, the transducer common is connected to the barrier's earth ground. Since the transducer common is also connected to the power input common inside the 1900/27, care must be taken to avoid a ground loop which could arise from connecting the power input common to earth ground. Note that the approval drawings for the 89129 and 190520 Accelerometers require that the total earth ground loop impedance at the barrier be less than one ohm.

DRAWING TITLE DRAWING NUMBER NUMBER OF SHEETS

1900/27 Installation Approval Drawing 124919 2 CSA Intrinsically Safe Approval Drawing 107585 1

Documents

Vibration Monitor