K type thermocouple Working principle

The k type thermoelectric electromotive force signal is converted into the temperature of the measured medium through the electrical instrument (secondary instrument).The basic principle of k type thermocouple temperature measurement is that two conductors of different components form a closed loop. When there is a temperature gradient at both ends, there will be a current passing through the loop. At this time, there is an electromotive force --K type thermocouple thermoelectric electromotive force between the two ends, which is called seebeck effect.Two different components of the homogeneous conductor is a hot electrode, the temperature of the higher end for the working end, the temperature of the lower end for the free end, the free end is usually at a constant temperature.According to the function relation between K type thermoelectric electromotive force and temperature, the K type thermocouple indexing meter is made.Indexing meter is free end temperature at 0℃ under the condition of different K type thermocouple has different indexing meter.

When the third metal material is connected to the K type thermocouple circuit, as long as the temperature of the two contacts of the material is the same, the thermoelectricity generated by the K type thermocouple will remain unchanged, that is, it will not be affected by the third metal access circuit.Therefore, in K type thermocouple temperature measurement, can be connected to the measuring instrument, measured thermoelectric emf, you can know the temperature of the measured medium.