13
9.
Electrical wiring
Precautions on electrical wiring
Warning:
Electrical work should be done by qualified electrical engineers in accordance
with “Engineering Standards For Electrical Installation” and supplied
installation manuals. Special circuits should also be used. If the power circuit
lacks capacity or has an installation failure, it may cause a risk of electric
shock or fire.
1. Be sure to install an earth leakage breaker to the power.
2. Install the unit to prevent that any of the control circuit cables (remote controller,
transmission cables) is brought in direct contact with the power cable outside the
unit.
3. Ensure that there is no slack on all wire connections.
4. Some cables (power, remote controller, transmission cables) above the ceiling
may be bitten by mice. Use as many metal pipes as possible to insert the cables
into them for protection.
5. Never connect the power cable to leads for the transmission cables. Otherwise
the cables would be broken.
6. Be sure to connect control cables to the indoor unit, remote controller, and the
outdoor unit.
7. Put the unit to the ground on the outdoor unit side.
8. Select control cables from the conditions given in page
13
.
9. Perform wiring in compliance with the safety regulations detailed in
UL60335-2-40.
Caution:
• Be sure to put the unit to the ground on the outdoor unit side. Do not
connect the earth cable to any gas pipe, water pipe, lightening rod, or
telephone earth cable. Incomplete grounding may cause a risk of electric
shock.
• If the supply cord is damaged, it must be replaced by the manufacturer, its
service agent or similarly qualified persons in order to avoid a hazard.
Transmission cable specifications
Transmission cables
ME Remote controller cables
MA Remote controller cables
Type of
cable
Shielding wire (2-core)
CVVS, CPEVS or MVVS
Use UL wire rated 300 V.
Sheathed 2-core cable (CVV, shielded
CVVS, CPEVS or MVVS)
Use UL wire rated 300 V.
Sheathed 2-core cable
Use UL wire rated 300 V.
Cable
diameter
More than 1.25 mm
2
[AWG 16]
0.3 – 1.25 mm
2
[AWG 22 – 16]
(0.75 – 1.25 mm
2
[AWG 18 –16])*
1
0.3 – 1.25 mm
2
[AWG 22 – 16]
(0.75 – 1.25 mm
2
[AWG 18 –16])*
1
Remarks
Max length: 200 m [656 ft]
Maximum length of transmission lines for centralized control and indoor/outdoor
transmission lines (Maximum length via indoor units): 500 m [1640 ft] MAX
The maximum length of the wiring between power supply unit for
transmission lines (on the transmission lines for centralized control) and each
outdoor unit and system controller is 200 m [656 ft].
When 10 m [32 ft] is exceeded, use
cables with the same specification as
transmission cables.
Max length: 200 m [656 ft]
*1 Connected with simple remote controller.
CVVS, MVVS: PVC insulated PVC jacketed shielded control cable
CPEVS: PE insulated PVC jacketed shielded communication cable
CVV: PVC insulated PVC sheathed control cable
9.1. Power supply wiring
•
Use dedicated power supplies for the outdoor unit and indoor unit.
•
Bear in mind ambient conditions (ambient temperature, direct sunlight, rain water, etc.) when proceeding with the wiring and connections.
•
The wire size is the minimum value for metal conduit wiring. If the voltage drops, use a wire that is one rank thicker in diameter. Make sure the power-supply voltage does
not drop more than 10%.
•
Specific wiring requirements should adhere to the wiring regulations of the region.
•
Power supply cords of appliances shall not be lighter than design 245 IEC 57, 227 IEC 57, 245 IEC 53 or 227 IEC 53.
•
A switch with at least 3 mm contact separation in each pole shall be provided by the Air conditioner installation.
•
Wiring size must comply with the applicable local and national codes.
•
Use copper supply wires.
Use UL wires rated 300 V or more for the power supply cords.
•
Install a ground wire longer than other cables.
•
To ensure all-pole-disconnection from the main power supply, make sure to provide a disconnection incorporated in the fixed wiring routed to the unit during installation.
[Fig. 9.1.1] (P.5)
A
Ground-fault interrupter
B
Local switch/Wiring breaker
C
Indoor unit
D
Pull box
Total operating current of the Indoor unit
Minimum wire thickness (mm
2
/AWG)
Breaker for wiring (NFB)
Ground-fault interrupter *
1
Main cable
Branch
Ground
Capacity
Fuse
F0 = 15 A or less *
2
2.1/14
2.1/14
2.1/14
15
15
15
15 A current sensitivity *
3
F0 = 20 A or less *
2
3.3/12
3.3/12
3.3/12
20
20
20
20 A current sensitivity *
3
F0 = 30 A or less *
2
5.3/10
5.3/10
5.3/10
30
30
30
30 A current sensitivity *
3
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 indoor unit 1)/C} + {V1 × (Quantity of indoor unit 2)/C} + {V1 × (Quantity of indoor unit 3)/C} +
…
Indoor unit
V1
V2
PEFY-P·NMAU-E4
18.6
3.0
