9. 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 install an earth leakage breaker to the power.
2. 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.
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 mouses. 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. Other-
wise the cables would be broken.
<Table 1>
System configuration
Transmission cable length
Facility example
(for noise judgment)
Types of transmission
cables
Length
2. Remote controller cables
Types of cables
Cable diameter
Length
9.1. 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. 9.1.1] (P.4)
A Switch 16 A
C Indoor unit
D Total operating current be less than 16 A
E Pull box
[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 mal-
function or fire.
Downloaded from
www.Manualslib.com
Less than 120 m
Residence or independent store
without noise
VCTF, VCTFK, CVV, CVS, VVR,
VVF, VCT or shielding wire
CVVS or CPEVS
MA remote controller
Sheathed 2-core cable (unshielded) CVV
0.3 to 1.25 mm
2
Less than 200 m
2
B Overcurrent protection 16 A
manuals search engine
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 11 .
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.
Types of control cables
1. Wiring transmission cables
•
Types of transmission cables
Design wiring in accordance with the following table <Table 1>.
•
Cable diameter
More than 1.25 mm
For a single-refrigerant system
Building, clinic, hospital or communications
station without noise supposedly generated
from inverter equipment, private power gen-
erator, high-frequency medical equipment,
radio-used communications equipment and
so on
Shielding wire CVVS or CPEVS
Less than 120 m
Sheathed 2-core cable (unshielded) CVV
0.3 to 1.25 mm
Add any portion in excess of 10 m to within the longest allowable trans-
mission cable length 200 m (Shielding portion is more than 1.25 mm
9.2. Connecting remote controller, indoor
and outdoor transmission cables
•
Connect indoor unit TB5 and outdoor unit TB3. (Non-polarized 2-wire)
The "S" on indoor unit 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 con-
troller.
•
Connect the "1" and "2" on indoor unit TB15 to a MA remote controller. (Non-
polarized 2-wire)
•
Connect the "M1" and "M2" on indoor unit TB5 to a M-NET remote controller.
(Non-polarized 2-wire)
•
Connect the remote controller's transmission cable within 10 m using a 0.75mm
core cable. If the distance is more than 10 m, use a 1.25 mm
[Fig. 9.2.1] (P.4) MA Remote controller
[Fig. 9.2.2] (P.4) M-NET Remote controller
A Terminal block for indoor transmission cable
B Terminal block for outdoor transmission cable
C Remote controller
•
DC 9 to 13 V between 1 and 2 (MA remote controller)
•
DC 24 to 30 V between M1 and M2 (M-NET remote controller)
[Fig. 9.2.3] (P.5) MA Remote controller
[Fig. 9.2.4] (P.5) M-NET Remote controller
A Non-polarized
C Remote Controller
•
The MA remote controller and the M-NET remote controller cannot be used at
the same time or interchangeably.
Caution:
Install wiring so that it is not tight and under tension. Wiring under tension
may break, or overheat and burn.
2
For a multi-refrigerant system
More than 120 m
Regardless of length
All facilities
Less than 200 m
M-NET remote controller
2
B TB15
D TB5
2
)
2
2
junction cable.
11