Mitsubishi MXZ-8A140VA, Installation Manual

Page: 13 / 16

13
WIRING SPECIFICATIONS
(OUTDOOR-BRANCH BOX CONNECTING CABLE)
Cross section of cable
Round
Flat
Flat
Round
Wire size (mm 2 )
2.5
2.5
1.5
2.5
Number of wires
3
3
4
4
Polarity
Clockwise : S1-S2-S3
* Pay attention to stripe of yellow and green
Not applicable
(Because center wire has no cover finish)
From left to right : S1-Open-S2-S3
Clockwise : S1-S2-S3-Open
*Connect S1 and S3 to the opposite angle
L (m)*6
(50)
*2
Not applicable
*5
(45)
*3
(55)
*4
*1 : Power supply cords of appliances shall not be lighter than design 245 IEC or 227
IEC.
*2 : In case that cable with stripe of yellow and green is available.
*3 : In case of regular polarity connection (S1-S2-S3), wire size is 1.5 mm
2 .
*4 : In case of regular polarity connection (S1-S2-S3).
*5 : In the flat cables are connected as this picture, they can be used up to 55 m.
*6 : Mentioned cable length is just a reference value.
It may be different depending on the condition of installation, Humidity or materi-
als, etc.
S1 S2 S3
(3C Flat cable
×
2)
Be sure to connect the outdoor-branch box/indoor-branch box connecting cables directly to the units (no intermediate connections).
Intermediate connections can lead to communication errors if water enters the cables and causes insufficient insulation to ground or a poor electrical contact at the
intermediate connection point.
(If an intermediate connection is necessary, be sure to take measures to prevent water from entering the cables.)
7. Electrical work
S1
S2
S3
S1
S2
S3
S1
S2
S3
S1
S2
S3
Power supply
Outdoor unit
Isolator (Switch)
3 poles isolator (Switch)
“A-control”
Indoor unit
Branch
box
Warning:
In case of A-control wiring, 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 outdoor unit and branch box/indoor unit and branch box, please use 3-poles type.
Caution:
After using the isolator, be sure to turn off and on the main power supply to reset the system. Otherwise, the outdoor unit may not be able to detect the branch
box(es) or indoor units.