Methods for anti-interference of platinum rhodium thermocouples

Methods for preventing annoyance of platinum rhodium thermocouples:

When using the reference terminal grounding method, the platinum rhodium thermocouple (or compensating wire) is output to one end and grounded through a sufficiently large capacitor (if possible, the larger the capacitor, the better). The measurement end grounding method is to ground the measurement end of the thermocouple, which means that a metal wire is led out from the measurement end of the thermocouple and grounded. This method has a good preventive effect on the disturbance of low-temperature power leakage. When selecting metal wires, one should choose wires that are resistant to low temperatures and harmful to thermocouple electrodes.

In the application process of thermocouples, there are always many situations that disturb our measurement. This is a difficult achievement, and we need to prepare for such situations when applying thermocouples. With the progress of the current industrial production level, the application rate of thermocouples is constantly increasing, so the measurement length of thermocouples is an event worth paying attention to!

What should we do when our thermocouple encounters troublesome situations during the application process?

Barrier method: Thread the compensating wire of the thermocouple into an iron pipe or other metal barrier to stop the barrier. This can avoid electromagnetic interference and high-voltage electric field interference. When applying this method, the iron pipe and barrier should be properly grounded, and the compensating wire should be twisted together.

Cut off method: It is to suspend the thermocouple device so that the thermocouple does not fight against the refractory bricks on the furnace wall, and insulation is also used between the thermocouple and the bracket to stop cutting off. This method can effectively prevent the disturbance of low-temperature power leakage.

Grounding method: This method involves grounding the measurement circuit to prevent interference and ensure the measurement accuracy of the instrument. There are two situations for this method: * the thermocouple reference terminal is grounded, and the second is the thermocouple measurement terminal grounded.