Viessmann VITOCAL 300-G Installation And Service Instructions Manual page 221

Overview of the PCBs and connection options
Main PCB with extension (operational components 230 V~)
2.
sYH
1 2
U
sXÖ
N ? N L1
M
1 2 3 4 1 2 3 4
sXA sXS sXD
sYÖ
1 2
N N
? ?
1.
1.
1.
F3 Fuse 6.3 A (slow)
fÖ Factory connection
sYG sYF
2.
2.
r
2.
N N N N
?
? ? ?
1 2 3 4 5 6 7
sXF
sYA sYS
1 2 3 4 5 1 2 3 4
M
N
N N
?
1.
r
NC
Connection and wiring diagrams
(cont.)
M2
r
N
N
N?
?
a:C]
c
1 2 3
sXG
sYD fÖ
N N
? ?
A1
AC
sYÖ Factory connection
sYA/sYS On site connections
M2
N
?
M
Ù
F3
6.3 A (slow)
N
221