Drain Piping Work; Connecting Electrical Connections; Electrical Wiring - Mitsubishi Electric CITY MULTI Série Manuel D'installation

9.2. Drain piping work

1. Ensure that the drain piping is downward (pitch of more than 1/100) to the
outdoor (discharge) side. Do not provide any trap or irregularity on the way.
(1)
2. Ensure that any cross-wise drain piping is less than 20 m [65-9/16] (excluding
the difference of elevation). If the drain piping is long, provide metal braces to
prevent it from waving. Never provide any air vent pipe. Otherwise drain may
be ejected.
3. Use a hard vinyl chloride pipe VP-25 (with an external diameter of 32 mm [1-1/4])
for drain piping.
4. Ensure that collected pipes are 10 cm [5/16] lower than the unit body's drain
port as shown in 2.
5. Do not provide any odor trap at the drain discharge port.
6. Put the end of the drain piping in a position where no odor is generated.
7. Do not put the end of the drain piping in any drain where ionic gases are
generated.
[Fig. 9.2.1] (P. 3)
A Downward slope 1/100 or more
B Drain hose
C Unit
D Collective piping
E Maximize this length to approx. 10 cm [5/16]

9.3. Connecting electrical connections

Verify that the model name on the operating instructions on the cover of the control
box is the same as the model name on the nameplate.
Step 1
Remove the screws holding the terminal box cover in place.
[Fig. 9.3.1] (P. 3)
A Screws
C Control box

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, or external input/output line) is brought in direct con-
tact 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, or external input/
output line) above the ceiling may be bitten by mouses. Use as many metal
pipes as possible to insert the cables into them for protection.
1. Transmission cables
PWFY-P36NMU-E-BU
Transmission cables
Shielding wire (2-core)
Type of cable
CVVS, CPEVS or MVVS
More than 1.25 mm
Cable diameter
AWG 16
AWG No
Remarks
PWFY-P36/P72NMU-E-AU
Transmission cables
Shielding wire (2-core)
Type of cable
CVVS, CPEVS or MVVS
More than 1.25 mm
Cable diameter
AWG 16
AWG No
Remarks
10
B Front panel
MA Remote controller cables
Sheathed 2-core cable (shielded)
CVVS
2 2
0.3 ∼ 1.25 mm (0.75 ∼ 1.25 mm
AWG 18 to 16
- Max. length : 200 m [656 ft]
MA Remote controller cables
Sheathed 2-core cable (shielded)
CVVS
2 2
0.3 ∼ 1.25 mm (0.75 ∼ 1.25 mm
AWG 18 to 16
- Max. length : 200 m [656 ft]
Note:
Ensure that the wiring is not pinched when fitting the terminal box cover.
Pinching the wiring may cut it.
Caution:
Install wiring so that it is not tight and under tension. Wiring under tension
may break, or overheat and burn.
• Fix power source external input/output line wiring to control box by using buffer
bushing for tensile force to prevent electric shock. (PG connection or the like.)
Connect transmission wiring to transmission terminal block through the knock-
out hole of control box using ordinary bushing.
• After wiring is complete, make sure again that there is no slack on the connec-
tions, and attach the cover onto the control box in the reverse order removal.
[Fig. 9.3.2] (P. 3)
A To prevent external tensile force from applying to the wiring connection section of
power source terminal block use buffer bushing like PG connection or the like.
B External signal input cable
C External signal output cable
D Power source wiring
E Tensile force
F Use ordinary bushing
G Transmission cable and MA remote controller cable
H Conduit
I Side frame
J Knockout hole (for power source wiring)
K Washer (accessory)
Caution:
Wire the power supply so that no tension is imparted. Otherwise disconnec-
tion, heating or fire result.
6. Never connect the power cable to leads for the transmission cables. Other-
wise the cables would be broken.
7. Be sure to connect control cables to the indoor unit, remote controller, and the
outdoor unit.
8. Be sure to ground the unit.
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 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>.
External input
Sheathed multi-core cable (shielded)
CVVS or MVVS
2 2
) 0.3 ∼ 0.5 mm
AWG 22 to 20
Max. length : 100 m [328 ft]
External input
Sheathed multi-core cable (shielded)
CVV or MVV
2 2
) 0.3 ∼ 0.5 mm
AWG 22 to 20
Max. length : 100 m [328 ft]
External output
Sheathed multi-core cable (unshielded)
CVV or MVV
2
0.3 ∼ 1.25 mm
AWG 22 to 16
Rated voltage : L1-N : 208/230 V
Rated load : 0.6 A
External output
Sheathed multi-core cable (unshielded)
CVV or MVV
2
0.3 ∼ 1.25 mm
AWG 22 to 16
Rated voltage : L1-N : 208/230 V
Rated load : 0.6 A