Mitsubishi Electric MSZ-FS18NA Manuel D'installation page 93

8. Electrical work
A
B
Fig. 8-1
F E G
D
Fig. 8-3
A
Electric cover
B
Rubber bush
C
Wiring
D
Controller board
E
Terminal block: TB5
F
Terminal block: TB2B <To outdoor unit>
G
Terminal block: TB3A-TB3E
<To indoor unit>
H
Earth Terminal <To outdoor unit>
Fig. 8-5
1.5 m or less
B
Fig. 8-7
C
B
Fig. 8-2
P
Q
R
H~O
Fig. 8-4
J
Earth Terminal <For TB3A>
K
Earth Terminal <For TB3B>
L
Earth Terminal <For TB3D>
M
Earth Terminal <For TB3C>
N
Earth Terminal <For TB3E>
O
Earth Terminal <To other branch box>
P
Cable clamp <For TB2B>
Q
Cable clamp <For TB3A-TB3E>
R
Cable clamp <For TB5>
C
A
B
*
D
Fig. 8-6
Support
► Cautions for electrical work.
Warning:
• Always use dedicated circuits with breakers, and at the rated voltage.
Power supply circuits with insuffi cient capacity, and bad workmanship
during installation, may result in electric shock or fi re.
Caution:
• Be sure to establish an earth. Do not earth the unit to a utility pipe,
arrester, or telephone earth.
Incomplete earth may cause electrical shock. A high surge current from
lightning or other sources may cause damage to the air conditioner.
• Use the specifi ed electrical wiring and ensure that it is connected prop-
erly, and that it is not under tension.
Failure to follow these requirements may result in broken wiring, heating,
or fi re.
► Before turning Branch Box on, be sure to set the switches.
► To turn the power on, turn on the Branch Box then the outdoor unit, in
that order.
(In case power supplies for Branch Box and outdoor unit are separated)
► Wiring connecting branch box and outdoor unit, and branch box and
indoor units, functions as both power supply and signal cable. Connect
this wiring in accordance with the terminal block numbers to ensure
correct polarity.
► Ensure that the appropriate refrigerant piping and electrical wiring are
connected to each indoor unit. Incorrect wiring will interfere with the
correct operation of the unit.
► Connect refrigerant pipes and connection wires to the appropriate ports
marked with matching alphabets (Ex. A, B, C, D, E) on this unit.
► Always fix each ground wire separately with a ground screw.
► To prevent that wiring installed in the ceiling is chewed by rats etc., it
should be installed in wiring conduit.
1. Remove the electric cover. (Fig. 8-1)
2. Pass the wiring into the branch box each wire in place with a wiring clamp.
3. Firmly connect each wire to the appropriate terminal block. (Fig. 8-8)
4. Set dip sw. (Refer to 8.3)
5. Replace the electric cover.
8.1. When using wiring conduit (Fig. 8-5,6,7)
Replace the horizontal cover when the wiring conduit has been fi xed in place.
A Cover
B Wiring conduit
C Washer
D Nut
Wiring conduit of up to 1" OD may be used.
(1) When using 1" OD wiring conduit, remove the bush and fi x to the branch box.
Remove the horizontal cover while fi xing to the branch box.
(2) When using wiring conduit of 3/4" OD or smaller, notch the bush and insert the
wiring conduit approximately 100 mm into the branch box.
* Replace the horizontal cover when the wiring conduit has been fi xed in place.
Caution:
To avoid excessive strain on the branch box, support the wiring conduit
with one or more support(s) 1.5 m or less from the branch box.
Refer to Fig. 8-7 as an example.
B
9