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7. Electrical wiring
Precautions on electrical wiring
Warning:
Electrical work should be done by qualified electrical engineers / electrician in accordance with
"Engineering Standards For Electrical Installation" and supplied installation manuals. Dedicated
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 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 any of the control circuit cables (remote controller, transmission cables) coming into direct contact with the power
cable outside 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 mice. Insert the cables into metal pipes for
protection.
6. Never connect the power cable to leads for the transmission cables. This will damage the transmission cable.
7. Be sure to connect control cables to the indoor unit, remote controller (when used), and the outdoor unit.
8. Ground the unit on the outdoor unit side.
9. Select control cables from the conditions given in page 10.
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.
Types of control cables
Wiring transmission cables
•
Types of transmission cables
Design wiring in accordance with the following table
•
Cable diameter
More than 1.25 mm
2
Connecting wiring
[Fig. 7.0.1] (P.5)
7.1. Power supply wiring
•
Power supply cords of appliances shall not be lighter than design 245 IEC 57 or 227 IEC 57.
•
A switch with at least 3 mm contact separation in each pole shall be provided by the Air conditioner installation.
Power cable size: more than 1.5 mm
[Fig. 7.1.1] (P.6)
[Selecting non-fuse breaker (NF) or 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 rated 15 A or 20 A.
NF model name (MITSUBISHI): NF30-CS (15 A) (20 A)
NV model name (MITSUBISHI): NV30-CA (15 A) (20 A)
Use an earth leakage breaker with a sensitivity of less than 30 mA 0.1 s.
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 malfu nction or fire .
7.2. Connecting remote controller, PQFY and outdoor transmission cables
(Remote controller is available as an option.)
A remote controller is required to perform initial setting. No remote controller is required after the initial setting provided that only heating or
cooling are required and there will be no need to change between the two modes or change the set point, The unit is designed to receive control
signals from other appliances via volt free contact. Initial setting can be performed using the ME or MA remote controllers. Other indoor units can have
ME remote controllers connected.
•
Connect PQFY controller TB5 and outdoor unit TB3. (Non-polarized 2-wire)
•
The "S" on PQFY controller TB5 is a shielding wire connection. For specifications about the connecting cables, refer to the outdoor unit
installation manual.
•
Install a remote controller following the manual supplied with the remote controller.
•
Connect the "1" and "2” on PQFY controller TB15 to an MA remote controller. (Non-polarized 2-wire)
•
Connect the "M1"and'M2' on PQFY controller TB5 to an M-NET remote controller. (Non-polarized 2-wire)
•
Connect the remote controller's transmission cable within 10 m using a 0.75 mm
2
core cable. If the distance is more than 10 m, use a
1.25 mm
2
junction cable. Note the remote controller can be located inside the outer cover of the unit if external changes to the mode and set
point are not desired.
