Electrical Wiring; Test Run; Before Test Run - Mitsubishi Electric PEH-P400MYA Installationshandbuch

10. Electrical wiring

Precautions on electrical wiring
Warning:
Electrical work should be done by qualified electrical engineers in accord-
ance with "Engineering Standards For Electrical Installation" and supplied
installation manuals. Special circuits should also be used. If the power cir-
cuit lacks capacity or has an installation failure, it may cause a risk of elec-
tric shock or fire.
1. Be sure to take power from the special branch circuit.
2. Be sure to install an earth leakage breaker to the power.
3. Install the unit to prevent that any of the control circuit cables (remote control-
ler, transmission cables) is brought in direct contact with the power cable out-
side the unit.
4. Ensure that there is no slack on all wire connections.
5. Some cables (power, remote controller, transmission cables) above the ceiling
may be bitten by mouses. Use as many metal pipes as possible to insert the
cables into them for protection.
6. Never connect the power cable to leads for the transmission cables. Otherwise
the cables would be broken.
7. Be sure to connect control cables to the indoor unit, remote controller, and the
outdoor unit.
8. Put the unit to the ground on the outdoor unit side.
9. Be sure to connect between the control cable terminal block of the outdoor unit
and that of the indoor unit. (Cables have polarity, so make sure that they are
connected according to the terminal numbers.)
10. Fix power source wiring to control box by using buffer bushing for tensible force
(PG connection or the like). Connect control wiring to control terminal bed
throngh the knockout hole of control box using ordinary bushing.
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 indoor unit
and outdoor unit, please use 3-potes type.
Caution:
Be sure to put the unit to the ground on the outdoor unit side. Do not con-
nect the earth cable to any gas pipe, water pipe, lightening rod, or telephone
earth cable. Incomplete grounding may cause a risk of electric shock.
[Fig. 10.0.1] (P.5)
A Power supply
C Power supply wiring for outdoor unit
D Power supply wiring for indoor unit
E Outdoor unit
G Connection wiring for indoor/outdoor units (polarity)
H Remote controller
I Connection wiring for indoor/remote controller (no polarity)
J Grounding
K Signal wiring for alternate defrost
L Wiring circuit breaker or isolating switch
[Fig. 10.0.2] (P.5)
A Indoor unit
C Control cable wiring
E Earth leakage breaker
G Power cable terminal bed
I Defrost signal cable terminal bed

11. Test run

11.1. Before test run

The test run can be carried out either from the outdoor unit or the indoor unit.
1. Checklist
•
After the installation, piping setup, and wiring of the indoor and outdoor units is
complete, check that refrigerant is not leaking, the power and control wires are
not loose, and the poles are not reversed.
•
Use a 500 V insulation resistance tester to make sure that the resistance be-
tween the power terminal and the ground is 1.0 MΩ or more. If it is less than
1.0 MΩ, do not operate the unit. * Absolutely do not touch the tester to indoor/
outdoor connection terminals S1, S2, and S3. An accident could occur.
•
Make sure there is no malfunction in the outdoor unit. (If there is a malfunction,
you can diagnose it using LED1 on the board.)
16
B Earth leakage breaker
F Indoor unit
B Power cable wiring
D Outdoor unit
F Wiring circuit breaker or isolating switch
H Control cable terminal bed
J Defrost signal cable wiring
Caution:
Make sure that refrigerant pipe and wiring unit must be connected from Out-
door unit No.1 to Indoor unit No.1 and Outdoor unit No.2 to Indoor unit No.2
respectively.
Wiring from Outdoor unit No.1 must be connected to terminal bed TB4-1 in
control box of Indoor unit No.1 while wiring from Outdoor unit No.2 must be
connected to terminal bed TB4-2 in control box of Indoor unit No.2.
Any mistakes on those connections may cause an abnormal refrigerant pipe
temperature and etc.
[Wiring example] (For metal piping)
Power Cable
PEH-P400MYA 1.5 mm 2 or thicker
PUH-P200MYA 4 mm 2 or thicker
2
PEH-P500MYA 1.5 mm or thicker
PUH-P250MYA 6 mm 2 or thicker
* The grounding wire must be of the same diameter as the power cable wires.
[Selecting earth leakage breaker (NV)]
To select NF or NV instead of a combination of Class B fuse with switch, use the
following:
• In the case of Class B fuse
Fuse (class B) 15 A
Earth leakage NV100-SW
breaker ELB 15 A
(with over-load protection) 30 mA 0.1s or less
NV is a product name of MITSUBISHI.
• Power supply cords of appliances shall not be lighter than design 245 IEC 53
or 227 IEC 53.
• Indoor unit/outdoor unit connecting cords shall not be lighter than design 245
IEC 57.
• A switch with at least 3 mm contact separation in each pole shall be provided
by the Air conditioner installation.
• The connection wiring between the outdoor and indoor units can be extended
up to a maximum of 80 m.
If 4 mm 2 used and S3 separated, Max. 50 m.
If 6 mm 2 used and S3 separated, Max. 80 m.
Caution:
Do not use anything other than the correct capacity breaker and fuse. Using
fuse, wire or copper wire with too large capacity may cause a risk of mal-
function or fire.
Location of cable holes
[Fig. 10.0.3] (P.5)
A For remote controller cables
B For outdoor unit connection cables
•
Check that the ball valve is fully open on both the liquid and gas ends.
•
Check the electrical power phase. If the phase is reversed, the fan may rotate
in the wrong direction or stop, or unusual sounds may be produced.
•
Starting at least 12 hours before the test run, send current through the
crankcase heater. (If the current is running for a shorter period of time,
damage to the compressor could result.)
• For specific models requiring changing of settings for higher ceilings or selec-
tion of power supply ON/OFF capability, make proper changes referring to the
description for Selection of Functions through Remote Controller.
After the above checks are complete, carry out the test run as indicated in the
following outline.
Remote
Breaker Defrost signal
Fuse controller
Capacity
Cable
cable
15 A 15 A –
Cable or
wire of 0.3
30 A 32 A 0.5 mm 2 or thicker
2
~ 1.25 mm
15 A 15 A –
(max. DC
12 V)
40 A 40 A 0.5 mm 2 or thicker
40 A 50 A
NV100-SW NV100-SW
40 A 50 A
100 mA 0.1s or less 100 mA 0.1s or less
C For power supply cables