Data Sheet for Product

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Siemens RDF302… Flush-mounted room thermostats with RS485 Modbus communications CE1N3079en
Smart Infrastructure 2020-02-21
Connection terminals
L, N Operating voltage AC 230 V
Q1 Control output “Fan speed 1 AC 230 V”
Q2 Control output “Fan speed 2 AC 230 V”
Q3 Control output “Fan speed 3 AC 230 V”
Y11,Y21 Control output “Valve” AC 230 V (N.O., for normally
closed valves), output for compressor or output for
electrical heater
X1, X2
1)
Multifunctional input for temperature sensor (e.g.
QAH11.1) or potential-free switch
Factory setting:
X1 = Operating mode switchover contact
X2 = External sensor
(function can be selected via parameter P38/P40).
M
1)
Measuring neutral for sensor and switch
+ RS485 Modbus connection
– RS485 Modbus connection
REF RS485 signal / common ground
(Differential common)
1)
RDF302.B does not have inputs X1, X2 and M.
Connection diagrams
Application
N1 Room thermostat RDF302...
M1 1- or 3-speed fan
V1 Valve actuator, 2- or 3-position
V1, V2 Valve actuator, 2-position
E1 Electric heater
C1, C2 1-stage compressor
S1, S2 Switch (keycard, window contact,
presence detector, etc.)
B1, B2 Temperature sensor (return air
temperature, external room
temperature, changeover sensor, etc.)
+ RS485 Modbus connection
- RS485 Modbus connection
REF RS485 signal/common ground
(Differential common)
RDF302.B does not have inputs X1, X2 and M.
2-pipe, 2-position
2-pipe, 3-position
2-pipe
& electric heater
4-pipe
1-stage compressor
(heating and/or
cooling)
1-stage compressor
& electric heater
L
N
10 A
L
N
Y11
Y21
AC 230 V
X1
M
X2
N1
M1
V1
5(2)A
Max.
5(2)A
Max.
B2
S2
B1
S1
3
1
7
1
A
1
2
Q1 Q2 Q3
I II III
+ -
REF
V1
5(2)A
Max.
E1
5(2)A
Max.
5(2)A
Max.
V1
C1
5(2)A
Max.
V1
5(2)A
Max.
V2
5(2)A
Max .
C1
5(2)A
Max.
E1
5(2)A
Max.
C2
5(2)A
Max.
+
-