Viessmann VITOLIGNO 300-C Installation And Service Instructions Manual page 47

Vitoligno 300-C Installation/Service
Electrical Connections
Legend
A DIN rail X2 boiler junction box
B Mixing valve extension module (accessory)
Legend
S1 Rotary selector
F1 MCB/fuse
(continued)
Mixing valve extension kit (accessory)
Max. 3 mixing valve extension kits can be connected to
the boiler control unit (accessory). Each extension kit must
be connected to the PCB KSK via KM-BUS; see page 146.
Connections per extension kit
Connections For
Sensor connections HC, WWB (return
temperature sensor)
WWB (tank
temperature sensor)
Pump connection HC, WWB
Mixing valve motor HC, VSB
connection
The distinctiveness and sequence of the extension kits
must be defined via rotary selector S1 in the extension kit.
Extension kit
E1
E2
E3
Allocation of connections
Note: For a detailed overview of connection options,
see page 48.
PCB HKK
1x HC at A1
2x HC at A1 and A2
3x HC at A1, A2 and A3
Note: Max. 4x HC can be connected in total.
If 0x HC or 1x HC: WWB at A2
If 2x HK: WWB at A3
Note: Always connect WWB
immediately downstream of
HC without a gap.
Exception: If only WWB is
connected to the HKK, connect
it at A2.
ZP only at A2 or A3
ZP possible in addition to WWB
SOL only at A3
It is not possible to connect solar control module type

SM1.
Solar at the boiler only possible if WWB or the buffer

tank (3-5 sensors) are connected to the Ecotronic.
Refer to the mixing valve extension module
Installation Instructions for additional information.
Installation
Connection
numbers in
extension kit
2
17
20
52
S1 rotary selector position
1
3
5
Extension kits
1x HC at E1
2x HC at E1 and E2
3x HC at E1, E2 and E3
WWB at E1, E2 or E3
Note: Connect WWB
downstream of HC
without a gap.
VSB possible in
addition to WWB
47