Mitsubishi Electric CITY MULTI PUHY-P108 Service Handbook page 31

[ II Restrictions ]
SW4-7:OFF (Compressor ON/OFF, NIGHT MODE)
CN3D 1-3P
Open
Short-circuit
SW4-7:ON (STEP DEMAND)
CN3D 1-3P
Note the following steps to be taken when using the STEP DEMAND
(Example) When switching from 100% to 50%
Demand control
steps
If the step listed as the wrong example above is taken, thermo may go off.
The percentage of the demand listed in the table above is an approximate value based on the
compressor volume and does not necessarily correspond with the capacity.
Example of wiring connection
CN51
Remote controller board
Relay circuit
X
L
1
Y
L
2
Field-installed
L1 : Error indicator lamp/freeze prevention output
L2 : Compressor operation display lamp
X,Y : Relay (For 12V DC coil rating 0.9 W or below)
CN3D
Remote controller board Relay circuit
SW1
X
SW2
Y
Field-installed
SW1 : NIGHT MODE command or Compressor ON/OFF
SW2 : Compressor ON/OFF command
X,Y : Relay (Contact Minimum applied load 12V DC 1 mA)
Compressor ON/OFF
OFF
ON
Open
Short-circuit
(Wrong) 100%
(Correct) 100%
Controller board on
outdoor unit
5
X
CN51
4
Y
3
Maximum allowable wiring length = 10 m
Controller board on
outdoor unit
1
X CN3D
2
Y
3
Maximum allowable wiring length = 10 m
CN3D 1-2P
Open
Short-circuit
CN3D 1-2P
Open
100% (not on the
on-DEMAND control)
0%
0% 50%
75% 50%
CN3S
Snow sensor
X
Insulation
Field-installed
Maximum allowable wiring length = 10 m
X: Snow sensor (
Contact Minimum applied load 12V DC 1 mA
- 22 -
NIGHT MODE
OFF
ON
Short-circuit
75%
50%
Controller board on
outdoor unit
1
CN3S
2
3
)