How is the free end temperature thermocouple fixed

Thermocouple cold end and hot side, you said that the free end is refers to the display part of

when the thermocouple temperature measurement meter basic with temperature compensation function, no longer need for temperature compensation.

when the application of sensors and secondary instrument connection must use the same degree, compensating lead wires.

two different ingredients of conductor ( Called the thermocouple wire or hot electrode) Two ends synthesis loop, when two junction temperature is not at the same time, in the circuit will generate electromotive force, this kind of phenomenon called the thermoelectric effect, and the electromotive force called thermoelectric potential. Thermocouple is to use the principle of temperature measurement, which directly used for measuring the medium temperature is called at the end of the working side ( Also known as the measuring end) , on the other side called cold end ( Also known as compensation) ； The cold end connected to the display instrument or meter, display instrument will point out the thermocouple thermoelectric potential.

free end is the thermocouple cold end. The cold end through the compensation wire transfer to the temperature control instrument ( Namely to think of compensation conductor should be as the extension of thermocouple section of the line) , temperature control instrument has a thermal resistance measuring instrument circuit of temperature. So the cold end temperature is not fixed.

hypothesis temperature measurement end 825, 25, the cold end temperature difference in temperature is 800 degrees, 800 degrees can produce a corresponding voltage, temperature control instrument convert the voltage to 800 degrees, combined with its own measurement environment temperature 25 degrees, show 825 degrees.

the same if the environment temperature to 45 degrees, so the cold end temperature is 45 degrees, the temperature is 780 degrees, the meter is ( 825 - 45) + 45, is still show 825 degrees.