Wiring Specifications; Indoor Unit Power Supplied From Outdoor Unit; Simultaneous Twin System - Mitsubishi Electric SUZ-KA24NAHZ Service Manual

8

WIRING SPECIFICATIONS

8-1. INDOOR UNIT POWER SUPPLIED FROM OUTDOOR UNIT

The following illustrations show available connection patterns.
The outdoor unit power supply patterns vary on each model.
1:1 System
C
L1
A B L2
GR
D
S1
S2
S3
G
Affix a label A that is included with the manuals near each wiring diagram for the indoor and outdoor units.
Outdoor model name
Outdoor unit power supply
Breaker size
Minimum circuit ampacity
Maximum rating of overcurrent protective device
Wiring Outdoor unit power supply
Wire No. x Outdoor unit power supply earth
size Indoor unit-Outdoor unit
Indoor unit earth
Remote controller-Indoor unit
Circuit Outdoor unit L1-L2
rating Indoor unit-Outdoor unit S1-S2
Indoor unit-Outdoor unit S2-S3
Remote controller-Indoor unit
Please follow applicable federal, state, or local codes to prevent potential leakage/electric shock. Or install a ground fault interrupt for
the prevention of leakage and electric shock.
*1. Maximum 147 ft [45 m].
If AWG13 used, maximum 164 ft [50 m].
If AWG13 used and S3 separated, maximum 262 ft [80 m].
*2. The 30 ft [10 m] wire is attached in the remote controller accessory. Maximum 1500 ft [500 m].
*3. The figures are NOT always against the ground.
S3 terminal has 24 VDC against S2 terminal. However between S3 and S1, these terminals are NOT electrically insulated by the transformer
or other device.
Notes: 1. Wiring size must comply with the applicable local and national code.
2. Use copper supply wires.
3. Use wires rated 600 V or more for the power supply cables and the indoor/outdoor unit connecting cables.
4. Install an earth line longer than power cables.
Outdoor Unit
Warning:
In the 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 indoor unit and
outdoor unit, please use 3-pole type.
• Turn on the main power when the ambient temperature is, −4°F [−20°C] or higher.
• In below, −4°F [−20°C] condition, it needs at least 4 h standby to operate in order to warm the electrical parts.
OCH754A

Simultaneous twin system

F
A B
S1
S2
S3
1
E
2
2 × Min AWG 12
1 × Min AWG 12
*1 3 × AWG 14 (polar)
1 × Min AWG 14
*2
*3
*3
*3
*3
208/230 V
Single phase
Isolator
S1
A-Control
S2
S3
F F
C
L1
L2
GR
D
S1 S1 S1
S2 S2 S2
S3 S3 S3
1 1
E
2 2
G
KA24
Single, 208/230 V, 60 Hz
25 A
17 A
27 A
2 × AWG 22
(Non-polar)
208/230 VAC
208/230 VAC
24 VDC
12 VDC
3 poles isolator
17
A Outdoor unit power supply
B Wiring circuit breaker or isolating switch
C Outdoor unit
D Indoor unit/outdoor unit connecting cords
E Remote controller
F Indoor unit
G Indoor unit earth
G
KA30
35 A
24 A
40 A
2 × Min AWG 10
1 × Min AWG 10
3 × AWG 14 (polar)
1 × Min AWG 14
2 × AWG 22
(Non-polar)
208/230 VAC
208/230 VAC
24 VDC
12 VDC
S1
A-Control
S2
Indoor Unit
S3
KA36
26 A
42 A