A temperature transmitter for thermocouples and RTDs is an electronic device
that converts the small voltage (from a thermocouple) or resistance change (from an RTD)
into a standardized output signal, usually 4–20 mA, which can be read by a control
system or data logger.

Key Features

1. Input Types

  • Thermocouple (TC): measures millivolt signal generated by the thermocouple junction.
  • RTD (Resistance Temperature Detector): measures resistance changes, usually of Pt100, Pt1000, or other RTD types.

2. Signal Conversion

  • Converts mV (TC) or Ω (RTD) into a linearized, calibrated signal proportional to temperature.
  • Often includes cold-junction compensation for thermocouples.

3. Output Signals

  • Most common: 4–20 mA (loop-powered).
  • Other options: 0–10 V, digital (HART, FOUNDATION Fieldbus, Modbus, Profibus).

4. Mounting

  • DIN rail,Head-mounted or Field-mount (directly on thermowell or sensor connection head).

5. Features

  • Linearization and scaling for thermocouples and RTDs.
  • Cold-junction compensation (for thermocouples).
  • Loop-powered or separately powered.
  • Optional explosion-proof or intrinsically safe versions for hazardous areas.