Viessmann VITOCAL 300-G PRO Installation And Service Instructions Manual page 68

Installation sequence
Overview of electrical connections
Terminals Function
ST. 223.1 Central fault message
ST. 223.2
U
Controller and sensor PCB
X6
F4
aVG
F3
F2 F7
F0 F6
X24
X5
X31
68
F14 F20
F8 F13 F18
F12
F16 F21
(cont.)
Explanation
Floating contact:
■ Closed: Fault
■ Open: No fault
■ Not suitable for safety LV.
Connection values (contact rating):
■ Voltage: 230 V~
■ Max. switching current: 4(2) A
On-site connection, see separate "Con-
nection and wiring diagram" sheet 21.
Note
■ No parameters need to be set.
■ The contact issues a short pulse when
the power supply is switched on. Ob-
serve the pulse when processing the
message via communication tools.