Electrical Wiring - Mitsubishi Electric MXZ-8A140VA1 Technical & Service Manual

10

ELECTRICAL WIRING

External wiring procedure (Fig.1)
E Power supply: Single phase 220/230/240V, 50Hz 220V, 60Hz,
Max. Permissive system Impedance : 0.22(")
Note:
1 Power supply input: Outdoor unit only. Connect the lines (C), (D) in accordance with the terminal block names to ensure
correct polarity.
2 As for lines (C), S1 and S2 are for connecting the power source. And S2 and S3 are for signals. S2 is a common cable for
the power source and signal.
(A) Main power
(B) Earth line
line
6.0 mm² 6.0 mm²
When using twisted wire for the wiring, the use of round terminal is required.
w1 Max 45 m ("Outdoor unit-Branch box
Notes: 1. Wiring size must comply with the applicable local and national code.
2. Power supply cords and Indoor unit/Branch box/Outdoor unit connecting cords shall not be lighter than polychloro-
prene sheathed flexible cord. (Design 60245 IEC 57)
3. Install an earth line longer than power cables.
Warning:
There is high voltage potential on the S3 terminal caused by electrical circuit design that has no electrical insulation between
power line and communication signal line. Therefore, please turn off the main power supply when servicing. And do not touch
the S1, S2, S3 terminals when the power is energized. If isolator should be used between indoor unit, branch box and outdoor
unit, please use 3-pole type.
<Example>
(In case of 2- branch boxes)
Outdoor unit
(A) (A)
L
N
Circuit
(C)
breaker
S1
(B)
S2
S3
(C)
Wire diameter
(C) Signal line/ (D) Signal line/
Earth line
1.5 mm² 1/
Min. 1.5 mm²
# 1" plus "branch box
Fig.1
Branch box #1
(5- branch type)
Indoor unit
TB3A
(D)
S1 S1
S2 S2
S3 S3
TB2B TB3B
(D)
S1 S1 S1
S2 S2 S2
S3 S3 S3
TB3C
(D)
S1 S1
S2 S2
S3 S3
TB3D
(D)
S1 S1
S2 S2
S3 S3
TB3E
(D)
S1 S1
S2 S2
S3 S3
TB3A
(D)
S1 S1
S2 S2
S3 S3
TB3B
(D)
S1 S1
TB2
S2 S2
S1
S3 S3
S2
S3
TB3C
(D)
S1 S1
S2 S2
S3 S3
Branch box #2
(3- branch type)
Interrupting
current
Earth line
1.5 mm²/
40 A
Min. 1.5 mm²
# 1-Branch box # 2"). If 2.5 mm² used, Max 55 m.
Warning:
Be sure to connect the power supply cords and connecting
wires for the indoor units, outdoor units, branch boxes
directly to the units (no intermediate connections).
A ROOM
Intermediate connections can lead to communication errors
in the cords or wires and causes insufficient insulation to
ground or a poor electrical contact at the intermediate con-
nection point.
B ROOM
(If an intermediate connection is necessary, be sure to take
measures to prevent water from entering the cords and
wires.)
C ROOM
IMPORTANT
Make sure that the current leakage breaker is one com-
D ROOM
patible with higher harmonics.
Always use a current leakage breaker that is compat-
ible with higher harmonics as this unit is equipped
with an inverter.
E ROOM
The use of an inadequate breaker can cause the incor-
rect operation of inverter.
F ROOM
G ROOM
H ROOM
75
Breaker
Performance
characteristic
40 A, 30 mA
for 0.1sec. or less