8
Electrical wiring
8.1 General connection and safety
instructions
For the MVT devices, an electrical supply must be
laid as a mains supply to the outdoor unit as well
as a 4-core control line from the indoor unit to the
outdoor unit.
We recommend that screened control lines are
used with a minimum cross-section of 1.5 mm².
DANGER!
All electrical installation work is to be performed
by specialist companies. Disconnect the power
supply when connecting the electrical terminals.
NOTICE!
The electrical connection for the units must be
made at a separate feedpoint with a residual
current device in accordance with local regula-
tions and should be laid out by an electrician.
We recommend using shielded wires for the
control lines.
8.2 Outdoor unit connection
Before you start to connect, note the following
instructions:
n
Customers should install a terminal box in the
vicinity of the outdoor unit. We recommend
using a main/repair switch (Figure 9).
n
Voltage is supplied to the indoor unit through
the connecting line between the outdoor com-
ponent and indoor unit.
n
Details concerning the electrical protection of
the system are provided in the technical data.
Observe the required diameters!
n
If the outdoor unit is installed on a roof, ensure
it is protected against lightning strikes.
n
Label the electrical control lines and the asso-
ciated refrigerant pipes of each indoor unit with
the same letter (A to D).
n
Only connect the lines to their associated con-
nections as labelled with the same letter.
Mixing up the assignment of control lines and
refrigeration pipes can lead to fatal conse-
quences such as compressor damage!
Proceed as follows to connect the line:
1.
Remove the side panel at the connection.
2.
Choose the cable cross-section in accord-
ance with the relevant specifications.
3.
Feed both cables through the edge protec-
tion rings on the fixed connection panel.
4.
Connect the control line to the corresponding
terminals. Pay attention to the alignment of
the circuits.
5.
Fix the line in the strain relief and re-
assemble the unit.
Additional probe and control lines may be
required on some indoor units.
Check all plugged and clamped terminals to
verify that they are seated correctly and make
permanent contact. Tighten as required.
Fig. 21: Outdoor unit connection
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