Temperature Transmitter

Temperature transmitter using thermocouple, thermal resistance as a temperature measuring element, from the temperature measuring element output signal to the transmitter module, after stabilizing filter, operation amplification, nonlinear correction, V/I conversion, constant current and reverse protection circuit processing, converted into a linear relationship with the temperature of 4 ~ 20mA current signal 0-5V/0-10V voltage signal, RS485 digital signal output.

PCT Thermocouple Temperature Transmitter

Working principle of temperature transmitter

  • Temperature Measurement: The temperature sensor converts the temperature change into an electrical signal.
  • Signal amplification and processing: The circuit inside the transmitter amplifies the weak electrical signals and carries out filtering, linearization and other processing to improve the quality of the signals.
  • Analog to digital: the analog signal is converted to a digital signal for subsequent processing.
  • Digital Signal Processing: Calibration, compensation and other processing of digital signals to improve measurement accuracy.
  • Digital to analog: Convert the digital signal to a standard 4-20mA current signal.
  • Signal output: output the converted 4-20mA current signal and connect it to the control system.

The role of the temperature transmitter

  • Signal conversion: amplify and convert the weak signal output from the temperature sensor into a standard industrial control signal.
  • Isolation protection: isolate the sensor and control system to prevent interference and damage.
  • Signal linearization: Compensate for the non-linear characteristics of the temperature sensor output, improve measurement accuracy.
  • Signal transmission: Transmit the temperature signal to a farther distance, convenient for centralized control.

Components of temperature transmitter

  • Sensor input: Connect the temperature sensor and receive the temperature signal.
  • Signal processing circuit: amplify, filter and linearize the temperature signal.
  • Power supply circuit: provide working power for the transmitter.
  • Output circuit: Convert the processed signal into a standard 4-20mA current signal.

Classification of temperature transmitter

Classified by sensor type

  • Thermocouple transmitter: suitable for measuring high temperature.
  • RTD transmitter: suitable for measuring low and medium temperatures with high accuracy.

Classified by output signal

  • 4-20mA current output: the most common output method.
  • Digital signal output: such as HART protocol, FOUNDATION Fieldbus protocol and so on.

Categorized by structure

  • Integrated transmitter: sensor and transmitter are integrated.
  • Split transmitter: sensor and transmitter are separated.

Applications of Temperature Transmitters

  • Industrial process control: control boiler water temperature, reactor temperature, etc..
  • Environmental monitoring: monitoring atmospheric temperature, water temperature, etc..
  • Food processing: control the temperature of food processing, such as pasteurization, drying and so on.
  • Petrochemical: monitoring pipeline temperature, tank temperature, etc..