Analysis of the advantages and disadvantages of LABOM resistance thermometer

　　

Analysis of the advantages and disadvantages of LABOM resistance thermometer:

A、 advantage

(1) Widely used in industry to measure temperatures between -200 and 850 ℃, it has a high cost performance ratio; In rare cases, low temperatures can be measured up to 1K and high temperatures up to 1000 ° C.

(2) Thermoelectric resistors made of similar materials may not have the same upper limit as thermocouples for temperature measurement, but they have good stability and high accuracy in the medium and low temperature regions, and do not require cold junction temperature compensation. The signal is easy to transmit remotely

(3) Compared with thermocouples, at the same temperature, it has high sensitivity, large output signal, and is easy to measure.

(4) The accuracy of the standard platinum resistance thermometer is high, and it is used as an interpolation standard thermometer within the range of 13.8033-1234.93K.

B、 shortcoming

(1) Not suitable for measuring high-temperature objects.

(2) There are significant individual differences among different types of electric limit thermometers. The sensing element structure of copper resistance thermometers is complex, with large hysteresis and thermal inertia, making them unsuitable for measuring the temperature of objects with small volumes and temperature transients; Poor interchangeability of semiconductor thermistors, etc.

Classification of resistance thermometers

According to their applications, they can be divided into standard resistance thermometers and industrial resistance thermometers.

According to their structure, they can be divided into ordinary thermal limit thermometers, Kaizhuang thermal resistance thermometers, and thin film thermal resistance thermometers.

According to the material of the temperature sensing element, it can be divided into metal thermistor thermometers and semiconductor thermistor limit meters.

Practice has shown that for most metals, the resistance increases by 0.4% to 0.6% for every 1 ℃ increase in temperature; When the temperature rises by 1 ℃, the resistance of semiconductor thermistor will change by 2% -6%. Obviously, the sensitivity of semiconductor thermistor is higher than that of metal, but its reproducibility and stability are poor, and each one needs to be calibrated separately. Therefore, the application of semiconductor resistance thermometer is still limited to some extent.