Template for the Siemens RDF302 room thermostat over Modbus RTU. It reads room temperature and room setpoint, and allows remote writing of the room setpoint for climate control.
Key readings
Room Temperature
Room Setpoint
Available commands
Room Setpoint
Use cases
Monitor room temperature across multiple Siemens RDF302 thermostats on a single cloud dashboard.
Adjust room setpoints remotely without sending a technician to the building.
Create an alert when room temperature deviates more than 2 degrees from the active setpoint.
Schedule setpoint changes for office zones based on working hours and occupancy.
Log historical room temperature data for energy audits and comfort reporting.
Installation
1Wire the Siemens RDF302 to the Modbus RTU bus using a twisted pair cable connected to the A and B terminals on the thermostat.
2Set a unique Modbus slave address on each RDF302 using the on-device configuration menu.
3Configure the serial port on the ModbusCloud gateway (MCG or MLP series) to 19200 baud, even parity (8E1).
4Import the Siemens RDF302 template from the ModbusCloud template library and assign the correct slave address.
5Verify communication by checking that room temperature and setpoint values appear on the ModbusCloud dashboard.
Things to watch for
Registers (2)
2 read / 1 write
Name
Address
Function
Type
Unit
Access
Room Temperature
1002
FC04
uint16
ºC
R
Room Setpoint
102
FC03
uint16
R/W
Use directly in ModbusCloud
Import this template into your own portal with one click, or get in touch for installation support.