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1-70
TROUBLESHOOTING
“RUN” light flickers and “ALARM” is indicated on the remote control switch.
The unit No., alarm code and the unit code is alternately indicated on the set temperature section,
and the unit No. and alarm code are indicated on the display of the outdoor unit PCB.
This alarm code is indicated when the instantaneous overcurrent tripping occurs 3 times including 3
in 30 minutes. Retry operation is performed up to the occurrence of 2 times.
Conditions:
Inverter current is 150% of the rated current.
1*): Regarding replacing or the checking method for the diode module, refer to page 1-113.
2*): Regarding the checking method for transistor module, refer to page 1-112.
3*): Regarding the checking of inverter components, refer to page 1-111 regarding electrical discharge.
Alarm
Code
Protection Activation Against Instantaneous Overcurrent of Inverter (2)
(For 5 to 20HP)
Is the compressor
running current as
same as rated
current?
Is it (a)V more
during operation
when other devices
are operating?
Check the diode
module. *1)
Is it (a)V or more
during operation?
Replace the inverter
circuit board.
Replace the inverter
circuit board.
Restart operation.
Does it trip soon?
Are the input currents
of three phases nearly
equal? ( 3%)
+
_
Replace the
transistor module.
Yes
Yes
Yes
Yes
Yes
Yes
Yes
It trips.
No
No
No
No
No
No
No
No
No (Input currents out of balance.)
It trips
immediately.
Faulty
Faulty
Faulty
Good
Good
Good
Is the supply voltage
380-415V
±
10% or
220V
±
10%?
Check the inverter
circuit board. *3)
Check the
compressor.
Check the power
source capacity.
Is there any cause
of instantaneous
voltage decrease?
Check the transistor
module. *2)
It trips
occasionally.
It trips
occasionally.
It trips after a
certain period.
It trips after a
certain period.
Turn off power and
disconnect U, V, W
from compressor
terminals.
Turn ON #1 of DSW1
on PCB3 and restart.
Does it trip?
Check the
compressor.
Replace the diode
module.
Replace the inverter
circuit board.
Check the power
supply.
Check the capacity
and wiring of the
power source.
Replace the inverter
circuit board.
Yes (Input currents nearly equal (
±
3%).)
220V 60Hz
320
170
380-415V 50Hz
380V 60Hz
Power Supply
Mark (a)