Panasonic U-72MF1U9, Service Manual

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PCB and Functions
2. Indoor Unit Control PCB
1
2
3
4
5
6
7
8
By using the heater-driving signal of the indoor unit Control PCB, the external heater can be controlled as a united heating system
with the indoor unit. Also, by changing the EEPROM setting of the indoor unit, the external heater can be operated, even when
there is an alarm occurred on the system.
(1) Make sure to install protective devices like thermal fuse, thermal switch or current fuse with the heater.
The PCB of the indoor unit just output operation signal, and does not recognize, whether there is danger
or not on the heater side.
We can not take responsibility on the damage occurred on the heater side.
(2) Be sure to follow the Electrical Wiring Instruction as shown below and the Local Code.
A heater can potentially cause serious damage or fire. Please be careful to wire it with a best manner.
(3) Be sure to provide an independent power supply for the external heater, which is separate from the power
supply for the indoor unit.
(4) If there is a failure of the indoor unit Control PCB or indoor unit fan motor, the indoor unit stops outputting
heater signal.
(5) When Wring
ELECTRICAL SHOCK CAN CAUSE SEVERE PERSONAL INJURY OR DEATH. ONLY A QUALIFIED,
EXPERIENCED ELECTRICIAN SHOULD ATTEMPT TO WIRE THIS SYSTEM.
Do not supply power to the unit until all wiring and tubing are completed or reconnected and checked.
CAUTION
How to connect external heater
Model : S-**MF, S-**ME, S-**MP, S-**MR
(1) The output signal is 230V AC.
(2) When installing the heater, be sure to turn OFF
the power to the indoor unit.
(3) If it is wired to the connectors other than the
heater output terminal, by mistake, the heater
signal can not be output correctly.
(4) The connector for this output is separately sold
by the following part code: 623 312 1390
Make connection inside the electrical component
box.
1 2
RY
RED WHT
CN304(WHT)
External heater
Electrical component box
for indoor unit
Heater drive
signal wiring A
*1
AC230V 500mA
Wiring
connection
*
Wiring inside the electrical component box of the
indoor unit should be carried out referring to the
wiring diagram of each model.
Since it is necessary to wire to the high-voltage
electrode, separate from the low-voltage. *1
*
1 2
Heater output terminal
(CN304 WHT)
Model : S-**MU, S-**MY, S-**MD, S-**MT, S-**MM
2 1
Heater output terminal
(CN340 BLK)
*2
1
RED
+DC12V
2
RY
WHT
GND
Electrical component box
for indoor unit
CN340(BLK)
External heater
Heater drive
signal wiring B
DC12V 50mA
Wiring
connection
*
Heater output terminal
(CN340 BLK)
2 1
Only for S-**MY
Continued
2-9. Instructions for Connecting External Heater to VRF Indoor Units
SM830202-00̲3WAY VRF.indb 18 SM830202-00̲3WAY VRF.indb 18 2012/01/30 14:53:41 2012/01/30 14:53:41