Viessmann VITOCAL 300-G PRO Installation And Service Instructions Manual page 72

Installation sequence
Power supply
■ Technical connection require-
ments specified by the local
power supply utility
■ Protect the power supply to the
heat pump control unit with an
MCB/ fuse of max. 16 A.
Danger
The absence of component
earthing can lead to serious injury
from electric current if an electri-
cal fault occurs.
■ Always remake all earth con-
nections inside the heat pump.
■ Heat pump and pipework
must be grounded to the equi-
potential bonding of the build-
ing.
Danger
Incorrect core allocation can
result in serious injury and dam-
age to the appliance.
Never interchange cores "L" and
"N".
■ In negotiations with your power supply
utility, different supply tariffs for the
main power circuits may be offered.
Observe the technical connection
requirements of the power supply util-
ity.
■ If the compressor and/or instantane-
ous heating water heater (if installed)
are operated at an economy tariff
(power-OFF), provide an additional
cable for the power-OFF signal from
the meter box to the heat pump control
unit.
72
(cont.)
■ The allocation of the power-OFF (for
compressor and/or instantaneous
heating water heater) is made via the
type of connection and by setting
parameters in the heat pump control
unit.
In Germany, the power supply can be
cut off for up to 3 x 2 hours per day
(24 h).
■ The control unit feed (heat pump con-
trol unit/PCB) must be supplied with
power without interruption by the
power supply utility; tariffs subject to
possible shutdown must not be used
here.
Install the power supply of the heat
pump control unit and the cable for the
power-OFF signal in accordance with
the separate "Connection and wiring
diagram".
■ Protect the power supply to the heat
pump control unit with an MCB/ fuse of
max. 16 A.
■ For accessories and external compo-
nents that are not to be connected to
the heat pump control unit, connect the
power supply on the same phase as
the heat pump control unit; we recom-
mend using the same MCB/fuse.
Connection to the same MCB/fuse
provides additional safety when the
power is switched off. Observe the
power consumption of the connected
consumers.