Troubleshooting of thermocouple assembly

Disassembling thermocouples is widely used, but some problems are inevitable during the application process. When taking care of the disassembly of thermocouples, experts from China Sensor Trading Network should also know how to deal with some rare problems. Let's introduce the troubleshooting of disassembling thermocouples.

Problem 1: The thermoelectric potential is smaller than the actual value

Possible cause: short circuit; Short circuit between terminals in thermocouple junction box; Compensate for the short circuit caused by insulation burnout in the wire; Compensate for the mismatch between wires and thermocouples; Compensate for the reverse connection between the wire and the thermoelectric dipole; Insufficient extraction depth and incorrect device position; The temperature transition at the cold end of the thermocouple is too high.

Disposal method: After review, if it is caused by moisture, it can be dried; If the insulation of the ceramic tube is poor, it should be replaced; Open the junction box and clean the wiring board with a brush; Insulate the short circuit or replace it with a new compensating wire; Replace with a compensating wire of the same example; Accurately connect from scratch; Change the status of the device and the depth of extraction; Replace the connecting wire of the thermocouple with a compensating wire to move the cold end away from the low-temperature zone.

Problem 2: The thermoelectric potential is greater than reality

Possible cause: compensating for the mismatch between the wire and thermocouple models; Insufficient depth of extraction or incorrect device position; Thermoelectric electrode transformation; There are disturbing signals entering; The reference temperature of the thermocouple is too high.

Solution: Replace the compensating wires of the same model; Change the device status or extraction depth; Replace the thermocouple; Reflect on the source of annoyance and eliminate it; Adjust the reference temperature or stop modifying.

Problem 3: The measuring instrument is unstable due to interference, sometimes intermittent and sometimes fluctuating

Possible cause: Poor operation of the thermoelectric electrode at the terminal post; Thermocouples have intermittent short circuits or intermittent grounding phenomena; The thermoelectric electrode has been broken or appears to be broken but not broken; The thermocouple device is not sturdy and produces oscillation; Compensate for grounding or intermittent short circuits in the wires.

Disposal method: Reconnect; Remove the thermoelectric electrode of the thermocouple from the maintenance tube, identify the problem and eliminate it; Replace with a new electrode; The device is sturdy; Identify the problem and eliminate it.

The above is a summary and disposal measures of some possible problems that may occur during the application process of dismantling thermocouples, as well as the causes that may lead to such problems. When eliminating the problems, it is necessary to combine the detailed situation of the problems for disposal.