Mar 23, 2022
Thermocouple is a sensor that measures temperature based on the thermoelectric effect, and is one of the commonly used temperature measuring elements.Here is going to introduce some ways to keep thermocouples away from interference when in using.
1. Barrier method
The barrier method is to suspend the thermocouple so that the thermocouple does not touch the the furnace wall of refractory bricks. Insulators are also used for blocking between the thermocouple and the bracket.
2. Shielding method
The shielding method is to shield the compensation wire of the thermocouple in an iron pipe or other metal shield. In this way, electromagnetic interference and interference of high-voltage electric fields can be avoided. When using this method, the iron pipe and shield should be well grounded, and the compensation wire should be twisted.
3. Grounding method
This method is to ground the measurement loop to ensure the measurement accuracy of the instrument. There are two ways to do this: the first is to ground the reference junction of the thermocouple, and the second is to ground the measuring junction of the thermocouple. When using the reference terminal grounding method, one end of the output terminal of the thermocouple (or compensation wire) is grounded through a large enough capacitor (the larger the capacitor, the better ). The measuring junction grounding method is to lead a metal wire from the measuring end of the thermocouple to ground. The metal wire is selected to be high temperature resistant and harmless to the thermocouple electrode.
When using thermocouples, do the above preparations to avoid interference, so that the measurement of thermocouples can be more accurate.
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