Emerson ROC827 instruction manual To test the thermocouple module

ROC827 Instruction Manual

Do not try to verify a thermocouple that is connected and actively being monitored by a ROC827 by measuring the voltage at the ROC827 terminal blocks.

It is suggested that you independently verify the process temperature, by using a certified thermometer in an adjacent thermowell, and then compare it to what the ROC827 is reading.

Equipment Required:

ƒMultimeter

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 test the thermocouple module:

1.Disconnect the thermocouple from the thermocouple module.

2.Generate the correct J or K signal using a multimeter and connect the wiring from the multimeter to the T/C module in the ROC827.

3.Verify the ROC is reading the generated temperature form the multimeter.

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

To test the thermocouple:

1.Disconnect the thermocouple from the ROC827.

2.Connect the thermocouple directly to the multimeter and verify the reading is correct by comparing it to a certified temperature measurement device connected to the process temperature the T/C is measuring.

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

Unintentional thermocouple junctions cause many measurement errors. Remember that any junction of two different metals will cause a junction. To increase the length of the leads from the thermocouple, use the correct type of thermocouple extension wire. Any connector must be made of the correct thermocouple material and correct polarity must be observed.

If the reading is off:

1.The type J or K thermocouples are selected on a per channel basis on the thermocouple module. Verify each channel on the ROC827 and make sure it is set for the type of thermocouple that you are using.

2.Ensure any plugs, sockets, or terminal blocks used to connect the extension wire are made from the same metals as the thermocouples and correct polarity is observed.

3.Verify all connections are tight.

Issued Mar-06 Troubleshooting 6-11