Data Sheet for Product

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Siemens RDF302… Flush-mounted room thermostats with RS485 Modbus communications CE1N3079en
Smart Infrastructure 2020-02-21
Applications for heat pump systems
*)
Application and output signal, DIP switches, diagram
1-stage compressor ON/OFF
(heating or cooling)
1
ON
2 3
1-stage compressor with electric
heater
(heating or cooling) ON/OFF
1
ON
2 3
3181S31
N1
T
B1
T
D3
3
1
8
1
S
3
2
N1T
E1
B1
T
D3
1-stage compressor ON/OFF
(heating and cooling)
1
ON
2 3
3181S35
N1
T
B1
T
D3
N1 Thermostat
Terminal Y11: Heating (H&C) or Heating/Cooling
Terminal Y21: Cooling (H&C)
B1 Return air temperature sensor or external room
temperature sensor (optional)
E1 Electric heater D3 Dewpoint sensor
*)
RDF302.B does not have inputs X1 and X2, so sensor B1 and B2 are not
included in RDF302.B application.