9/11
Siemens
Temperature Controller RRV851
CE1N2725en
Building Technologies
27.08.2007
Connection terminals
B1
Signal input (external sensor NTC)
M Signal
ground
D1, D2
Digital inputs
D_GND Digital
ground
HB+ HB–
Communication bus
L, N
AC 230 V supply
Q…
Digital outputs, AC 24…230 V, 6(4) A
Y…
Digital outputs, AC 24…230 V, 3(1) A
Connection diagrams
B
1
M
D
1
D
_G
N
D
D1
D
2
D2
H
B
+
H
B
-
H
B
+
H
B
-
L
N
Q
74
Q
84
Q
94
Q
71
1
2
3
F1
1
Y
1
1
Y
1
2
Y
1
4
Y
2
1
Y
2
2
Y
2
4
Y
3
4
Y
3
1
Y1
N1
N2
AC 230V
L
N
T
X
+
T
X
-
4
8
5
g
n
d
RS485
Y2
B1
F2
Y3
B1
External temperature sensor (optional) or pipe changeover sensor (application A8)
CR1
Compressor relay stage 1
CR2
Compressor relay stage 2
D1
Remote activation of Comfort mode
D2
Fault or emergency heating
F1 3-speed
fan
F1
External supply line fusing, max. 10 A
F2 1-speed
fan
N1 RRV851
controller
N2
QAX850 master room unit
RV Reversing
valve
Y1 Cooling
output
Y2 Heating
output
Y3
Auxiliary heating, emergency heating or 2
nd
stage cooling
Y4
Valve actuator, AC 24…230 V
Typical connection
