7. Electrical work
Thickness of Wire for Main Power Supply and On/Off Capacities
Model
NAXMPH36A142A
NAXMPH42A152A
NAXMPH48A182A
Outdoor Unit
NAXMMX48A182A
Indoor Unit
*1. 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.
IMPORTANT
If a current leakage breaker is used, it should be compatible with higher harmonics as this unit is equipped with an inverter. The use of an inadequate breaker
can cause the incorrect operation of inverter.
*2. Use copper supply wires. Use the electric wires over the rating voltage 300 V.
Total operating current of the indoor unit
F0 = 15A or less
*2
F0 = 20A or less
*2
F0 = 30A or less
*2
Apply to IEC61000-3-3 about max. permissive system impedance.
*1 The Ground-fault interrupter should support inverter circuit.
The Ground-fault interrupter should combine using of local switch or wiring breaker.
*2 Please take the larger of F1 or F2 as the value for F0.
F1 = Total operating maximum current of the indoor units × 1.2
F2 = {V1 × (Quantity of Type 1)/C} + {V1 × (Quantity of Type 2)/C} + · · · + {V1 × (Quantity of Type 7)/C}
Indoor unit
NAXAMT
A112A
NAXCKS
A112A
NAXDKS
A112A
NAXFKS
A112A
NAXUKS
A112A
NAXWPH
A112A
NAXWST
A112A
PEAD-A
AA
PLA-A
EA
BC)
Branch box (TAC-MKA
C : Multiple of tripping current at tripping time 0.01 s
Please pick up "C" from the tripping characteristic of the breaker.
<Example of "F2" calculation>
* Condition Branch Box × 2 + PLA-A
F2 = 5.1 × 2/8 + 19.8 × 5/8
= 13.65
*3 Current sensitivity is calculated using the following formula.
G1 = V2 × (Quantity of Type 1) + V2 × (Quantity of Type 2) + · · · + V2 × (Quantity of Type 7) + V3 × (Wire length [km])
G1
Current sensitivity
30 or less
30 mA 0.1 sec or less
100 or less
100 mA 0.1 sec or less
Wire thickness
1.5 mm
2
2
2.5 mm
4.0 mm
2
1. Use a separate power supply for the outdoor unit and indoor unit.
2. Bear in mind ambient conditions (ambient temperature,direct sunlight, rain water,etc.) when proceeding with the wiring and connections.
3. The wire size is the minimum value for metal conduit wiring. The power cord size should be 1 rank thicker consideration of voltage drops.
Make sure the power-supply voltage does not drop more than 10%.
4. Specific wiring requirements should adhere to the wiring regulations of the region.
5. Power supply cords of parts of appliances for outdoor use shall not be lighter than polychloroprene sheathed flexible cord (design 60245 IEC57). For exam-
ple, use wiring such as YZW.
6. Install an earth longer than other cables.
Warning:
• Please turn off the main power supply when servicing. And do not touch the B1, B2
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-pole type or 2-pole type.
(Please refer to figure below.)
• Turn on the main power when the ambient temperature is -20°C (-4°F) or higher.
• Under conditions of -20°C (-4°F), it needs at least 4hr stand by before the units
operate in order to warm the electrical parts.
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.
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.)
Never splice the power cable or the indoor-outdoor-branch box connection cable, otherwise it may result in a smoke, a fire or communication failure.
14
Minimum Wire Thickness
Power Supply
Main Cable
13.3 [AWG6]
208/230 VAC, 60Hz
8.4 [AWG8]
208/230 VAC, 60Hz
Minimum wire thickness (mm
Main Cable
Branch
2.1/14
2.1/14
3.3/12
3.3/12
5.5/10
5.5/10
Type
V1
V2
5
26.9
2.4
1
17.1
2.4
2
19.8
2.4
3
7.4
2.4
6
9.9
2.4
4
6.8
2.4
3
7.4
2.4
5
26.9
2.4
2
19.8
2.4
7
5.1
3.0
EA × 5, C = 8 (refer to right sample chart)
V3
48
56
66
Breaker for
(mm
[AWG])
2
Wiring
*1
Ground
*2
13.3 [AWG6]
50 A
8.4 [AWG8]
40 A
Refer to installation manual of indoor unit.
/AWG)
2
Ground-fault interruper
(if you use)
Ground
2.1/14
15 A current sensitivity
3.3/12
20 A current sensitivity
5.3/10
30 A current sensitivity
B1
Outdoor unit
B2
Breaker for Current
Minimum cir-
Leakage (if you use)
cuit ampacity
50 A 30 mA 0.1 sec.
42 A
or less
40 A 30 mA 0.1 sec.
37 A
or less
Local switch (A)
*1
Capacity
Fuse
15
15
*3
20
20
*3
30
30
*3
Sample chart
6000
600
60
10
1
0.1
0.01
1
2
3
Rated Tripping current (x)
2 poles isolator (Switch)
L1
L2
GR
Maximum rating of
over current protec-
tor device
50 A
50 A
Breaker for wiring
(NFB)
15
20
30
SAMPLE
4
6
8
10
20
C
Branch box