Viessmann WB2B 45 - Page 43

Control Connections
43
Electrical Connections (continued)
Power/Pump module electrical connectors
Legend
40
- Power supply
20A
- System pump
sA - DHW pump
sÖ - Boiler pump
sK - DHW recirculation pump
50
- Fault alarm output
143
- External blocking terminals 2-3
External demand terminals 1-2
External heating program
changeover terminals 1-2
The allocation of the function
“external heating program
changeover” is set via coding
address ’91’
144
- External 0-10V signal
145
- KM BUS to boiler control board
See Vitodens 200-W WB2B
Start-up/Service Instructions
for applicable system coding
information.
5418 909 v1.6
NL
143
28
L G NL2
NLNLNL
L1G N
50
2021
20A40
N
L
120/230
Transformer
145
144
143
Power/Pump module
1 2 3 1 2 3
1 2 3
1 2 3
145
144
1 2 3 1 2 3
50
2021
20A40
Fig. 37