Common sense of temperature transmitter

- Nov 26, 2020-

The integrated temperature transmitter has the advantages of simple structure, saving leads, large output signal, strong anti-interference ability, good linearity, reverse connection protection and current limiting protection, and reliable operation. The output of the integrated temperature transmitter is a unified 4-20mA signal, which can be matched with a computer system or other conventional instruments. The user can also make explosion-proof or fire-proof measuring instruments.

The integrated temperature transmitter is generally composed of a temperature probe (thermocouple or thermal resistance sensor) and a two-wire solid electronic unit. The temperature measuring probe is directly installed in the junction box in the form of a solid module to form an integrated transmitter. The integrated temperature transmitter is generally divided into two types: thermal resistance and thermocouple.

Thermal resistance temperature transmitter is composed of reference unit, R/y conversion unit, linear circuit, reverse connection protection, current limiting protection, V/I conversion unit, etc. After the temperature measuring resistance signal is converted to 0 and amplified, the linear circuit compensates for the non-linear relationship between temperature and resistance. After the V/I conversion circuit, it outputs a 4-20mA constant current signal linearly related to the measured temperature. 

Thermocouple temperature transmitter generally consists of reference source, cold junction compensation, amplification unit, linearization processing, V/I conversion, broken couple processing, reverse connection protection, current limiting protection and other circuit units. It is to amplify the thermoelectric potential generated by the thermocouple through cold junction compensation, and then eliminate the nonlinear error between thermoelectric potential and temperature by a linear circuit, and finally amplify and convert it into a 4-20mA current output signal. In order to prevent accidents caused by the failure of temperature control due to wire breakage in thermocouple measurement, there is no power-off protection circuit in the transmitter. When the thermocouple wire is broken or the connection is poor, the transmitter will output the maximum value (28mA) to make the meter cut off the power.

temperature transmitter


We recommend that you choose a temperature transmitter with both high precision and high stability. If you are interested, you can call us +86 18991346449 or email info@mrcsensor.com