If your Nordson unit is displaying a fault for the RTD and you have already verified all connections are secure, follow these steps to check the RTD Sensor:
Checking the RTD Sensor: ALWAYS WEAR PROPER SAFETY GEAR
First, find out the temperature of the RTD to perform this check properly.
- · Disconnect and lock out electrical power to the system.
- · For the RTD being checked, disconnect the cordset that supplies power to RTD.
- · Refer to Figure 11-7 or 11-8 as appropriate. With the RTD at a know temperature, us an ohmmeter to measure the RTD resistance at the RTD pins at the cordset connector.
- · Refer to Figure 11-9 to determine the correct resistance for the RTD base on its temperature.
- o If measured resistance is correct, the RTD is operating properly.
- o If measured resistance indicates an open circuit, continue to the next step.
- · Remove the cordset connector hood and check for loose RTD wires or wire connections. Tighten any loose connections.
- · Check the RTD resistance again. If the resistance is correct, the RTD is operating properly. If resistance indicates an open circuit, continue to next step.
- · Disconnect the RTD wire, measure the resistance across the wires and compare the results to Figure 11-9:
o If measured resistance is within appropriate range, reconnect the RTD wires, reinstall the cordset connector hood and recheck the resistance at the RTD pins on connector.
o If measured resistance is not within the appropriate range, replace the RTD.