Mitsubishi Electronics MUZ-GE80VA Air Conditioner User Manual


 
79
M How to check miswiring and serial signal error
Turn OFF inverter-controlled lighting
equipment.
Turn OFF the power supply and then
turn ON again.
Press EMERGENCY OPERATION
switch.
A
Is serial signal
error indicated 6
minutes later?
B
Yes
Reinstall
either the unit
or the light
away from
each other.
Attach a lter
on remote
control receiv-
ing section
of the indoor
unit.
No
Turn OFF the power supply.
Is there rated voltage in the power supply?
Yes
No
Turn ON the power supply.
Check the power supply.
Is there rated voltage between outdoor terminal block S1 and S2?
No
Check the wiring.
Press EMERGENCY OPERATION switch once.
Does the upper lamp of OPERATION INDICA-
TOR lamp light up? <Con rmation of the power
to the indoor unit>
Yes
No
Is serial signal error indicated 6 minutes later?
Yes
No
Is there any miswiring,
poor contact, or wire
disconnection of the
indoor/outdoor connect-
ing wire?
Yes
Correct them.
No
A
Turn OFF the power supply.
Check once more if the indoor/outdoor
connecting wire is not miswiring.
Short-circuit outdoor terminal block S2
and S3.
1
B
1. Miswiring may damage indoor electronic control P.C.
board during the operation.
Be sure to con rm the wiring is correct before the opera-
tion starts.
Turn ON the power supply.
Does the LED on the inverter P.C. board repeat "3.6-second-OFF and 0.8-sec-
ond-ON quick blinking"? 3
Yes
No
(Lighted
or not
lighted)
Replace the inverter P.C. board. 2
2. Be careful of the residual voltage of smoothing
capacitor.
Yes
3. Be sure to check this within 3 minutes after turning ON.
After 3 minutes, LED blinks 6 times. Even when the
inverter P.C. board is normal, LED blinks 6 times after 3
minutes.
Is the bus-bar voltage of the inverter P.C. board or the outdoor electronic control P.C. board normal?
(Refer to "TEST POINT DIAGRAM AND VOLTAGE" of the outdoor unit.)
Yes
No
Check of power supply.
(Refer to 11-5. .)
Replace the indoor power
P.C. board and the indoor
terminal P.C. board
Is there amplitude of 10 to 20 VDC between indoor terminal block S2
and S3? <Con rmation of serial signal>
Yes
Check the wiring.
If there are any error of the indoor/outdoor connecting wire:
such as the damage of the wire, intermediate connection,
and/or poor contact to the terminal block, replace the indoor/
outdoor connecting wire.
No
Is there 2 VDC or less between CN10A (+)
and JPG (GND)(-) on the indoor electronic
control P.C. board?
No
Yes
Is there 2 VDC or less between
CN10A
(+) and JPG (GND)(-) on
the indoor electronic control P.C.
board?
Is there 2 VDC or less between
CN10A (+) and JPG (GND)(-) on
the indoor electronic control P.C.
board?
Replace the indoor elec-
tronic control P.C. board.
No Yes No
Yes
Turn OFF the power supply.
Remove the short-circuit between outdoor terminal block S2 and S3.
Turn ON the power supply.
Is there rated voltage between indoor terminal block S1 and S2?
<Con rmation of power voltage>
Yes
No
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OBH532E