Data Sheet for Product

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Siemens RDF302… Flush-mounted room thermostats with RS485 Modbus communications CE1N3079en
Smart Infrastructure 2020-02-21
Technical data
Power supply Rated voltage AC 230 V
Frequency 50/60 Hz
Power consumption Max. 7 VA / 3.7 W
Caution
No internal fuse!
External preliminary protection with max C 10 A circuit breaker required in all cases.
Outputs Fan control Q1, Q2, Q3-N
Rating
AC 230 V
5 mA…5(2) A
STOP
Note!
Fans must NOT be connected in parallel!
Connect one fan directly, for additional fans, one
relay for each speed.
Control output Y11-N / Y21-N (N.O.)
Rating
AC 230 V
Max. 5(2) A
Caution
No internal fuse!
External preliminary protection with max C 10 A circuit breakers in the supply line
required in all cases.
Inputs Multifunctional input X1-M / X2-M
**)
Temperature sensor input:
Type
Temperature range
Cable length
Digital input:
Operating action
Contact sensing
Parallel connection of several thermostats
for one switch
Insulation against mains voltage (SELV)
NTC (3 kW at 25 °C)
0...49 °C
Max. 80 m
Selectable (NO / NC)
SELV DC 0...5 V / max 5 mA
Max. 20 thermostats per switch
4 kV, reinforced insulation
Function of inputs:
External temperature sensor, heating/cooling
changeover sensor, operating mode switch-
over contact, dew point monitor contact,
enable electrical heater contact, fault contact,
monitoring input
Selectable
X1: P38
X2: P40
Modbus Interface type RS485 Modbus RTU,
Wire (ref.): 16 AWG, 1 pair, shielded
serial line with 1.5 mm
2
and
length < 1200 m
Bus current Max. 50 mA
Modbus topology:
See Modbus manual (MODBUS over serial line specification and implementation
guide from http://www.modbus.org).