Electrical Connection Requirements - Viessmann BW 35 .AHT PW Series Installation And Service Instructions Manual

Power supply
(cont.)
Power supply for control circuit (230 V~) and power circuit (400 V~)
Make connection in accordance with the separate
"Connection and wiring diagram".

Electrical connection requirements

Note
The power connections must be carried out by an
authorised electrician in accordance with local regula-
tions.
Type
BW 352.AHT058
BW 352.AHT071
BW 352.AHT084
BW 352.AHT096
BW 352.AHT119
BW 353.AHT126
BW 353.AHT147
Power supply with power-OFF
Power-OFF without on-site load disconnection (delivered condition)
The power-OFF signal is connected directly to the heat
pump control unit via floating contact. The compres-
sors are shut down when power-OFF is enabled.
Electronic soft starter, type SMC
Electronic soft starter functions:
■ Monitoring the compressor mains feed
■ Reducing the compressor starting current during the
starting procedure (soft start)
Delivered condition:
■ Rotating field, phase asymmetry: 20 %
■ Max. compressor operating current I
compressor output
Overload protection
If the tolerance ranges of the electronic soft starter are
exceeded, the soft starter will automatically separate
the appliance from the mains.
Remove the cause if the relay has responded. The
relay does not need to be reset.
Main cable fuse pro-
tection
125 A
125 A
160 A
160 A
200 A
200 A
250 A
: Subject to
max
Note
■ The control circuit must be supplied with power with-
out blocking by the power supply utility, so a sepa-
rate power supply is required for the control circuit.
A separate power supply for the control circuit
■
necessitates a change to the internal wiring. This
may only be carried out by an electrical contractor
according to the connection diagram.
■ The control circuit power supply and the cable for the
power-OFF signal can be combined in a single
5-core cable.
Cable lengths in the heat pump plus wall clear-
ance:
Control circuit power supply (230 V~ if on
site)
Power circuit power supply (400 V~)
Additional connecting cables
Note
Observe the technical connection conditions of the rel-
evant power supply utility.
Starting characteristics
The starting characteristics are set at the DIP switches
behind the transparent protective flap of the electronic
soft starter. At the factory, the DIP switches are set to
suit the respective heat pump type.
Prior to commissioning, compare the DIP switch set-
tings with the details in the separate "Connection and
wiring diagram", and adjust if necessary.
Installation sequence
3 m
3 m
2.5 m
43