Data Sheet for Product

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Siemens RDF302… Flush-mounted room thermostats with RS485 Modbus communications CE1N3079en
Smart Infrastructure 2020-02-21
Use
Room temperature control (heating or cooling) in individual rooms and zones by
means of:
2-pipe fan coil units
2-pipe fan coil units with electrical heater
4-pipe fan coil units
Compressors in DX-type equipment
Compressors in DX-type equipment with electrical heater
The RDF302, RDF302/VB and RDF302.B controls:
One single or 3-speed fan
One or two on/off valve actuators
One on/off valve actuator and one 1-stage electrical heater
One 3-position valve actuator
One 1-stage compressor in DX-type equipment, or one 1-stage compressor with
electrical heater
Used in systems with:
Heating or cooling mode
Automatic heating/cooling changeover
Manual heating/cooling changeover
Heating and cooling mode (e.g. 4-pipe system)
The room thermostats are delivered with a fixed set of applications.
The relevant application is selected and activated during commissioning using one
of the following tools:
Local DIP switch and HMI
Modbus commissioning tools
Functions
Maintain room temperature via built-in temperature sensor or external room
temperature/return air temperature sensor
Changeover between heating and cooling mode (automatic changeover via local
sensor/bus or manual changeover)
Select application via DIP switches or commissioning tools
Select operating mode via operating mode button on the thermostat
Single speed or 3-speed fan control (automatic or manual)
Display current room temperature or setpoint in °C and/or °F
Minimum and maximum limitation of room temperature setpoint
Key lock (automatic, manual or via bus)
Two multifunctional inputs, freely selectable for:
- Operating mode switchover contact (keycard)
- Automatic heating/cooling changeover sensor
- External room temperature sensor or return air temperature sensor
- Dew point sensor
- Electrical heater enabled
- Fault input
- Monitor input for temperature sensor or switch status
Advanced fan control function, e.g. fan kick, fan start, selectable fan operation
(enable, disable or depending on heating or cooling mode)
Purge function together with 2-port valve in a 2-pipe changeover system
Reminder to clean filters