Viessmann Vitocal 300-G Installation And Service Instructions Manual page 176

Connection and wiring diagrams
PCB 1: Message and safety components
Function
Brine pressure limiter,
frost stat (fault message
from AC-Box)
External blocking / mixer
CLOSE
Power-OFF
Flow switch
176
Explanation
If both limiters are installed wire in
series:
Closed = safety chain has continu-
ity
Open = safety chain break; appli-
ance not operational
Either jumper or limiter(s) must be
connected
Breaking capacity 230 V~, 0,5 A
Delivered condition: No jumper
fitted
Connect zero volt contact on site:
Closed = blocking enabled
Open = no blocking
Breaking capacity 230 V, 0,1 A
Connect zero volt contact on site:
Closed = no blocking
Open = blocking enabled
Breaking capacity 230 V, 0,5 A
Delivered condition: Jumper fitted
Connect zero volt contact on site:
Closed = appliance operational
Open = appliance operational, fault
message via display
Breaking capacity 230 V, 0,1 A
Delivered condition: Jumper fitted
Contact not integrated into the
safety chain
(cont.)
Connection
1X3.9
1X3.8
1X3.2
1X3.14
or to exter-
nal exten-
sion H1
1X3.7
1X3.6
1X3.3
1X3.4