Mitsubishi Electric PUZ-HA24NHA1, Service Manual

Page: 67 / 128

67
OCH750A
Special function
(a) Low-level sound priority mode (Local wiring)
Unit enters into Low-level sound priority mode by external signal input setting.
Inputting external signals to the outdoor unit decreases the outdoor unit operation sound 3 to 4 dB lower than that of usual.
Adding a commercial timer or on-off switch contactor setting to the CNDM connector which is optional contactor for demand
input located on the outdoor controller board enables to control compressor operation frequency.
Note: The performance depends on the load of conditioned outdoor temperature.
How to wire
1) Make the circuit as shown above with adapter for external signal input (PAC-SC36NA).
2) Turn SW1 to on for Low-level sound priority mode.
Turn SW1 to off to release Low-level sound priority mode and normal operation.
(b) On demand control (Local wiring)
By performing the following modification, energy consumption can be reduced to 0–100% of the normal consumption.
The demand function will be activated when a commercially available timer or the contact input of an ON/OFF switch is added
to the CNDM connector (option) on the control board of the outdoor unit.
1
Complete the circuit as shown when using the external input adapter (PAC-SC36NA-E). (Option)
2
By setting SW7-1 on the control board of the outdoor unit, the energy consumption (compared to the normal consumption) can
be limited as shown below.
SW7-1 SW2 SW3 Energy consumption
Demand
function
ON
OFF OFF 100%
ON OFF 75%
ON ON 50%
OFF ON 0% (Stop)
CNDM
X
SW1
~
X
Max. 33 ft [10 m] including local wiring
SW1: Switch
X: Relay (Contact spec.: DC1mA)
Relay
supply
Red 3
Brown 2
Orange 1
Purchased locally
Adapter for external
signal input
(PAC-SC36NA)
Outdoor unit
controller board
3
2
1
Insulate this point securely as
this is not used.
<Low-level sound priority mode circuit>
A
Circuit diagram example
(Demand function)
B
On-site arrangement
X, Y: Relay
C
External input adapter
(PAC-SC36NA-E)
D
Outdoor unit control board
E
Maximum 10 m
F
Power supply for relay
A
SW2
SW3
Orange
1
3
Brown
Red
CNDM
Y
X
X Y
F
B
E
C D