Rotary temperature transmitters (RTTs)

RTTs with hollow, rotating and fixed mechanical parts allow this transmitter to be connected in different positions even in very tight spaces. Their simplicity allows endless customisation.

What is a rotating temperature transmitter?

A temperature transmitter is an interface between a temperature sensor and a display or control device. It works by converting a sensor output signal, which is non-linear, into a linear signal that can be sent over longer distances without degradation.

Main uses and applications of rotary temperature transmitters

Temperature transducers transform the physical quantity of temperature into an electrical signal, which is then transferred to a regulator. One of the most common applications is their use in fire alarms or in heating systems.

The advantages of rotary temperature transmitters (RTTs)

  • Self-calibrating, no need for on-site calibration even for spare parts.
  • Several self-tests are performed to ensure the accuracy of the measurement.
  • The fixed and rotating parts can be exchanged or replaced individually.
  • Quick troubleshooting thanks to simple coding for each output, with no need to disassemble the parts:           
Fault detection Reading
PT100 short-circuit 21,0 mA
PT100 open/broken 21,5 mA
No communication between the parts 22,0 mA
Measurement not reliable 22,5 mA


  • MODBUS with isolated RS485 (optional).
  • Output fully isolated from the power supply for improved noise immunity.
  • All integrated, no need for an external signal control board.
  • The installation will accept a margin of 10 mm between the rotating and fixed part.
  • Several support diameters are available.
  • Connections with bolts, screws, connectors or fasteners.
  • From 1 to 8 channels.

RTT performance

  • Range: 0 – 1,500 °C. (Configurable).
  • Power supply: 17-27Vac or 22-35Vdc; current 0.2A.
  • Output: Voltage: 4-20mA; common GND. Isolated from the power supply. (frequency or mV optional).
  • Accuracy: standard ±0.15 °C, (optional down to ±0.05 °C).
  • Resolution: 0.025 °C.
  • Material: PA66+FG30% and aluminium protective frame.
  • Maximum speed: 10,000 r.p.m.
  • Local temperature: 100°C max. for the rotating part. 80°C for the stationary part.
  • Installation: 1 mm to 10 mm (standard 4 mm).
  • Inputs: 1 Pt100 sensor α = 0.00385, P200, to 2 or 3 wires (others on request)

Order number

23.012 – RTT 3CH PT100 0-250°C 20mm 4-20mA MODBUS485

23.013 – RTT 1CH PT100 0-250°C 20mm 4-20mA

23.014 – RTT 1CH PT100 0-400°C 20mm 4-20mA

23.015 – RTT 1CH PT100 0-250°C 25mm CONN 4-20mA

23.016 – RTTFJI 2CH PT200 0-250°C 22mm 4-20mA (Compatible with Fuji Electric)

23.017 – RTTFJI 1CH PT200 0-300°C 22mm 1OUT FREQ 1OUT 4-20mA (Compatible with Fuji Electric)

Please contact E.D. Elettronica Dedicata for further information or customisation.


*requested fields

    I have read and accepted the Privacy Policy