Mitsubishi Electric M Series Installation Manual page 11

8. Electrical work
M-NET Branch BOX
(5-branches type)
TB3A
TB2B
S1
L
S2
N
S3
TB3B
S1
TB5
S2
M1
S3
M2
S
TB3C
S1
S2
S3
TB3D
S1
S2
S3
TB3E
S1
S2
S3
Fig. 8-9
A B
220/230/240 V
C
or
A B D
220/230/240 V
L N
C
TB2B
Fig. 8-10
Indoor unit
S1
A ROOM
S2
S3
S1
B ROOM
S2
S3
S1
C ROOM
S2
S3
• Recommended Connection Method
When connecting one indoor unit to the branch box, connect it to TB3A. When connecting
2 indoor units, connect them to TB3A and TB3B. When connecting 3 indoor units, connect
them to TB3A, TB3B, and TB3C. Connect indoor units in the order of A→B→C→D→E.
D
E C E C E
or or
M1 M2 L N M1 M2
E
S S
TB5 TB2 TB5 TB15
Note:
1
Connect the lines (B), (C) 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 common cable for the power source
and signal.
(A) Main power line/
Earth line
3-core 2.5 mm
2
When using twisted wire for the wiring, the use of round terminal is required.
Notes: 1. Wiring size must comply with the applicable local and national
code.
2. Power supply cords and indoor unit/branch box/outdoor unit con-
necting cords shall not be lighter than polychloroprene sheathed
flexible cord. (Design 60245 IEC 57)
3. Install an earth line longer than power cables.
4. Do not bundle the M-NET cable with the connection cable and
power supply cable.
It may cause erroneous operation.
3
Reactor BOX (Optional parts)
When the product is used for a purpose other than as professional equip-
ment, the Reactor BOX may be necessary.
Outdoor unit
1-phase power supply
3-phase power supply
Warning:
Never splice the cable, otherwise it may result in a smoke, a fi re or communi-
cation failure.
Power supply wiring (Supply power separately to branch box
and outdoor unit)
• Install an earth line longer than other cables.
• Power supply cords of appliance shall not be lighter than design 245IEC57 or
227IEC57, 245 IEC 53 or 227 IEC 53.
• A switch with at least 3 mm, 1/8 inch contact separation in each pole shall be
provided by the air conditioner installation.
[Fig. 8-10]
A
Ground-fault interrupter
B
Local switch/Wiring breaker
C
Branch Box
D
Pull box
E
1 2 M-NET CONTROL INDOOR UNIT
Wire diameter
(B) M-NETcable Shielding (C) Signal line/
wire CVVS, CPEVS or MVVS
2-core 1.25 mm 4-core 1.5 mm
2
Less Than 200 m Less Than 25 m
Branch box power supply method
Power supply from
Separate power supply
outdoor unit
Unnecessary Necessary
Necessary Necessary
Earth line
2
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