RDU50 is a room temperature controller with a liquid crystal display from Siemens Building Technologies for heating or cooling systems, with PI control, 0 to 10V output to the actuator, automatic cold/hot conversion, manual cold/hot conversion, operating modes: normal, energy-saving or off, operating mode conversion input, adjustable installation and control parameters, output reverse signal, display of room temperature and optional temperature values, minimum and maximum temperature set value limitation and other features.
This manual describes the functions of the RDU50 room temperature controller, including PI control, automatic or manual heating/cooling switching, and a LCD display of room temperature and setpoints. It also lists the supported output ranges (0‑10 V) and compatible devices such as VAV controllers and valve actuators.
Installation instructions cover mounting height, wiring, DIP switch settings, and sensor calibration. Parameter tables show how to adjust operating modes, temperature limits, and control gains, and explain how settings are retained after power loss.
| Power supply voltage | 24 V ±20% |
|---|---|
| Control output voltage range | 0–10 V DC |
| Maximum power consumption | 4 VA |
| Maximum relative humidity | <95 % RH |
| Storage temperature range | -20 to +70 °C |
| Weight | 0.23 kg |
It uses an automatic switching sensor (QAH11.1+ARG86.3) that measures water temperature; above 28 °C it switches to heating, below 16 °C it switches to cooling.
Set DIP2 to ON for normal polarity (0 V = 0 %, 10 V = 100 %) or to OFF for reversed polarity (0 V = 100 %, 10 V = 0 %).
Yes, all configured control parameters remain stored even when the power is cut.
Press the “+” and “‑” keys together for 3‑5 seconds, release, then press “+” for 3 seconds to display the parameter (e.g., P01). Use “+” and “‑” to adjust the value.