A temperature transmitter is an instrument that converts a temperature variable into a standardized output signal that can be transmitted, mainly used for the measurement and control of temperature parameters in industrial processes.
A temperature transmitter with a sensor usually consists of two parts: the sensor and the signal converter, which is used for automation safety. The sensor is mainly a thermocouple or thermal resistance; the signal converter is mainly composed of a measurement unit, signal processing, and a conversion unit.
Some temp transmitters have an additional display unit (intrinsically safe thermocouple transmitter), and some with Fieldbus function.
If the transmitter is composed of two sensors for measuring the temperature difference, there is a given continuous function relationship between the output signal and the temperature difference, that's why it is called a temperature transmitter. There is a certain continuous function relationship between the output signal of the temperature transmitter and the temperature variable. The output signal of the early-produced transmitter has a linear functional relationship with the resistance value of the temperature sensor.