ROC827 Instruction Manual

3.Measure the resistance across terminals + and . A reading of 0 (zero) ohms should be obtained. No continuity should be indicated.

4.Measure the resistance across the terminals + and –. The reading should indicate an open circuit.

6.3.8Troubleshooting Pulse Input Modules

Equipment Required:

ƒPulse Generator

ƒVoltage Generator

ƒFrequency Counter

ƒJumper wire

ƒPC running ROCLINK 800 software

Caution

Failure to exercise proper electrostatic discharge precautions, such as

wearing a grounded wrist strap may reset the processor or damage

 

electronic components, resulting in interrupted operations.

To verify high-speed operation:

1.Disconnect the field wiring at the PI module terminations.

2.Connect to ROCLINK 800 software.

3.Select Configuration > I/O > PI Points.

4.Select the correct Pulse Input Point Number.

5.Connect a pulse generator having sufficient output to drive the module to terminals L+ or H+ and COM. The pulse generator must synthesize a square wave signal of 50% for every cycle.

6.Connect a frequency counter across terminals L+ or H+ and COM.

7.Set the pulse generator to a value equal to, or less than 10 KHz.

8.Set the frequency counter to count pulses.

9.Verify, using ROCLINK 800 software, that the count read by the counter and the ROC827 are the same.

10.Remove the test equipment, and reconnect the field device.

6.3.9Troubleshooting RTD Input Modules

The RTD module is similar in operation to an Analog Input module and uses the same troubleshooting and repair procedures.

Equipment Required:

ƒMultimeter

ƒPC running ROCLINK 800 software

Issued Mar-06

Troubleshooting

6-9

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Emerson ROC827 Troubleshooting Pulse Input Modules, Troubleshooting RTD Input Modules, Equipment Required