Viessmann Vitocal 350-A Installation And Service Instructions Manual page 113

Power supply
(cont.)
The phase monitor switches off (switch-
ing contact opens) if these tolerances
are exceeded.
The phase monitor automatically re-ena-
bles the power supply if the values return
to within the specified tolerance range.
10
20
<>U
A
%
2
10
Asy
15
B
%
5
6
4
12
t
C
0.1
12
11
14
L3
L2
L1
A2
A1
Remove the cause if the relay has
responded. The relay does not need to
be reset.
A Over/undervoltage in %
H
B Phase asymmetry in %
<>U
C Switching delay in s
G
Asy
D Contact used in safety chain (N/O)
F
Ph
E Operating display ("Rel")
E
Rel
F Fault display phase failure/phase
G Fault display asymmetry ("Asy")
H Fault display over/undervoltage
LEDs explained
D
■ LED "Rel" illuminates green:
D
■ LED "Ph" illuminates red:
■ All LED's off:
■ LED "<>U" illuminates red:
■ LED "Asy" illuminates red:
Installation sequence
sequence ("Ph")
("<>U")
All voltages and the rotating field
(clockwise) are healthy.
The relay has responded; the rotating
field is anticlockwise.
One or several phases have dropped
out.
Incorrect voltage on one/several
phase(s).
Asymmetry on one/several phase(s).
113