2-26
Design of 2WAY SYSTEM
3. Electrical Wiring
3-1. General Precautions on Wiring
(1)
(2)
(3)
(4)
(5)
(6)
Before wiring, confirm the rated voltage of the unit as shown 
on its nameplate, then carry out the wiring closely following 
the wiring diagram.
Provide a power outlet to be used exclusively for each 
unit, and a power supply disconnect, circuit breaker and 
earth leakage breaker for overcurrent protection should be 
provided in the exclusive line.
To prevent possible hazards from insulation failure, the unit 
must be grounded.
Each wiring connection must be done in accordance with the 
wiring system diagram. Wrong wiring may cause the unit to 
misoperate or become damaged.
Do not allow wiring to touch the refrigerant tubing, 
compressor, or any moving parts of the fan.
Unauthorized changes in the internal wiring can be very 
dangerous. The manufacturer will accept no responsibility 
for any damage or misoperation that occurs as a result of 
such unauthorized changes. 
(7)
(8)
The remote control wiring and the inter-unit control wiring 
should be wired apart from the inter-unit power wiring.
Use shielded wires for inter-unit control wiring between units 
and ground the shield on both sides.
(9)
3-2. Recommended Wire Length and Wire Diameter for Power Supply System
Outdoor unit
(A) Power supply
Time delay fuse or 
circuit capacity
Wire size Max. length
U-8ME1E81 4 mm² 56 m 25 A
25 A
U-10ME1E81 4 mm² 46 m
U-12ME1E81 6 mm² 65 m 35 A
35 AU-14ME1E81 10 mm²
10 mm²
10 mm²
10 mm²
91 m
U-16ME1E81 75 m 45 A
U-18ME1E81 70 m 50 A
U-20ME1E81 58 m 50 A
or
(A) Power supply
Time delay fuse or 
circuit capacity
Wire size Max. length
6 mm² 84 m 35 A
6 mm²
6 mm²
69 m
65 m
35 A
35 A
10 mm²
10 mm²
10 mm²
10 mm²
91 m 50 A
75 m
70 m
58 m
50 A
50 A
50 A
Indoor unit
Type
(B) Power supply
Time delay fuse or
circuit capacity
2.5 mm²Minimum 2 mm²
Max. 150 m
Max. 130 m
Max. 150 m
Max. 130 m
Max.   60 m
Max. 30 m 10 – 16 A
10 – 16 A
15 A
15 A
K1
K2
Y2
D1, L1, U1, Y1, T1, 
F1, M1, P1, R1
E1 (73, 106, 140)
E1 (280)
E1 (224) Max. 50 m 10 – 16 A
10 – 16 A
10 – 16 A
Control wiring
(C) Inter-unit (between outdoor and indoor units) control wiring
or
2.0 mm² (AWG #14)
Use shielded wiring*
Max. 2,000 m
0.75 mm² (AWG #18)
Use shielded wiring*
Max. 1,000 m
(D) Remote control wiring
0.75 mm² (AWG #18)
Max. 500 m
NOTE
* With ring-type wire terminal.
(E) Control wiring for group control
0.75 mm² (AWG #18)
Max. 200 m (Total)
(F) Inter-outdoor unit control wiring
0.75 mm² (AWG #18)
Use shielded wiring
Max. 300 m
(10)
Regulations on wire diameters differ from locality to 
locality. For field wiring rules, please refer to your LOCAL 
ELECTRICAL CODES before beginning. You must 
ensure that installation complies with all relevant rules and 
regulations.
To prevent malfunction of the air conditioner caused by 
electrical noise, care must be taken when wiring as follows:
If the power supply cord of this appliance is damaged, 
it must be replaced by a repair shop appointed by the 
manufacturer, because special purpose tools are required.
Use a waterproof conduit for outdoor unit wiring to avoid 
damaging the wire and to prevent accumulation of liquid 
inside the unit.
TD831159-042WAYVRF.indb26TD831159-042WAYVRF.indb26 2014/08/2516:51:422014/08/2516:51:42