Advantages (1) It is cheap and easy to build ; As a result, it is widely used. (2) Different types of heat pairs are available for measuring from low temperature to high temperature. (3) It can be used to measure the temperature of a small object. (4) Since the thermal conductivity of warm joints is low, it can be used to measure the rapidly changing temperature. Disadvantages (1) Since there is no theoretical relationship over long temperature range, calibration of each heat pair is required for temperature measurement. (2) If the cooling junction is not at 0 ° C temperature, correction is required. (3) Neutral temperature measurement disturbs the limit.