Electrical Work; Setting Addresses And Operating Units; Test Run - Mitsubishi Electric CITY MULTI CMB-M-V-J1 Manuel D'installation

5. Electrical work

► Consult all related regulations and power companies beforehand.
Warning:
When air flow decrease is detected of a circulation fan beside the BC
controller installed at the height of less than 1.8 m from the ground, the
system must be powered off within 10 seconds from the detection. Before
powering off the system, connect the contactor to the power cable of the
outdoor unit and open the contactor.
Electrical work should be handled by qualified electrical engineers in
accordance with all related regulations and attached instruction manuals.
Special circuits should also be used. If there is a lack of power capacity or
a deficiency in electrical work, it may cause a risk of electric shock or fire.
► Connect all wires securely.
• Fix power source wiring to control box by using buffer bushing for tensile
force (PG connection or the like).
[Fig. 5.0.1] (P.6)
Ⓐ Control box
Power source wiring
Ⓑ
Ⓒ ø21 hole (closed rubber bushing)
Transmission wiring
Ⓓ
► Never connect the power cable to the terminal board for control cables.
(Otherwise it may be broken.)
► Be sure to wire between the control wire terminal boards for indoor
unit, outdoor unit and BC controller.
Use non-polarized 2-wire as transmission cables.
Use 2-core shielding cables (CVVS, CPEVS) of more than 1.25 mm
as transmission cables.

6. Setting addresses and operating units

The address switch of each BC controller is set to "000" when shipped from the
factory.
• Set the address switch to 1 + the address of the outdoor (heat source) unit.

7. Test run

Before commencing a test run please check the fol-
lowing:
► After installing, piping and wiring the indoor units and BC controllers,
check to see again that there is no refrigerant leakage and no slack on
power and control cables.
► Use a 500 V megger to check that there is an insulation resistance of
more than 1.0 MΩ between the power terminal block and the ground. If
it is less than 1.0 MΩ, do not operate the unit.
16
The switch capacity of the main power to BC controllers and the wire size are as
follows:
Switch (A)
Capacity
16
• For other detailed information, refer to the outdoor unit installation manual.
• Power supply cords of appliances shall not be lighter than design 245 IEC 53
or 227 IEC 53.
• A switch with at least 3 mm contact separation in each pole shall be provided
by the Air conditioner installation.
Caution:
Do not use anything other than the correct capacity fuse and breaker.
Using fuse, conductor or copper wire with too large capacity may cause a
risk of malfunction or fire.
Ensure that the outdoor units are put to the ground. Do not connect the
earth cable to any gas pipe, water pipe, lightening rod or telephone earth
cable. Incomplete grounding may cause a risk of electric shock.
in diameter
2
► The BC controller address should generally be set to 1 + the address of
the outdoor (heat source) unit. However, if this would result in it having
the same address as another outdoor unit, set the address between 51
and 100, making sure that it is different from the address of other BC
controllers.
• Please refer to the outdoor (heat source) unit installation manual.
Caution:
Never measure the insulation resistance of the terminal block for any
control cables.
Molded case Earth leakage
circuit breaker breaker
Fuse
20 A 30 mA
16 20 A
0.1 s or less
Wire size
1.5 mm
2