Mitsubishi Electric PUHZ-FRP71VHA Service Manual page 33

Abnormal point and detection method
Error Code
To find out the detail history (latest) about U9 error, turn ON SW2-1, 2-2, 2-6.
Detailed
Refer to 10-10.
codes
Overvoltage error
• Increase in DC bus voltage to
420V
01
Undervoltage error
• Instantaneous decrease in DC
bus voltage to 200V
02
Input current sensor error/
L1-phase open error
• Decrease in input current
through outdoor unit to 0.1A
only if operation frequency is
more than or equal to 40Hz
or compressor current is more
04
than or equal to 6A.
U9
(4220)
Abnormal power synchronous
signal
• No input of power synchronous
signal to power circuit board
• Power synchronous signal
of 44 Hz or less, or 65 Hz or
08
more is detected on power
circuit board.
PFC error (Overvoltage/
Undervoltage/Overcurrent)
• PFC detected any of the fol-
lowings
a) Increase in DC bus voltage
to 420V
b) Decrease in PFC control
10
voltage to 12V DC or lower
c) Increase in input current to
50A peak
PFC/IGBT error
(Undervoltage)
• When Compressor is running,
DC bus voltage stays at 310V
20
or lower for consecutive 10
seconds.
OCH544
Case
1 Abnormal increase in power source
voltage
2 Disconnection of compressor wiring
3 Defective outdoor power circuit
board
4 Compressor has a ground fault.
1 Decrease in power source voltage,
instantaneous stop.
2 Disconnection or loose connection
of CN52C on the outdoor noise f lter
circuit board/controller circuit board
3 Defective converter drive circuit of
outdoor power circuit board
4 Defective 52C drive circuit in outdoor
noise f lter circuit board
1 Disconnection or loose connection
between TB1 and outdoor noise f lter
circuit board
2 Disconnection or loose connection
of CN5 on the outdoor power circuit
board/CNCT on the outdoor noise
f lter board
3 Defective ACCT(AC current trans) on
the outdoor noise f lter circuit board
4 Defective input current detection
circuit of outdoor power circuit board
5 Defective outdoor controller circuit
board
1 Distortion of power source voltage,
Noise superimposition.
2 Disconnection or loose connection of
earth wiring
3 Disconnection or loose connection
of CN2 on the outdoor power circuit
board /controller circuit board
4 Defective power synchrous signal
circuit in outdoor controller circuit
board
5 Defective power synchrous signal
circuit in outdoor power circuit board
1 Abnormal increase in power souce
voltage
2 Decrease in power source voltage,
instantaneous stop.
3 Disconnection of compressor wiring
4 Misconnection of reactor (ACL)
5 Defective outdoor power circuit
board
6 Defective Reactor(ACL)
7 Disconnection or loose connection
of CN2 on the outdoor power circuit
board/controller circuit board
1 Incorrect switch settings on the
outdoor controller circuit board for
model select
2 Defective outdoor power circuit board
3 Defective outdoor controller circuit
board
33
Judgment and action
1 Check the field facility for the power
supply.
2 Correct the wiring (U . V . W phase) to
compressor. Refer to 10-9 (Outdoor
power circuit board).
3 Replace outdoor power circuit board.
4 Check compressor for electrical insula-
tion. Replace compressor.
1 Check the f eld facility for the power
supply.
2 Check CN52C wiring.
3 Replace outdoor power circuit board.
4 Replace outdoor noise f lter circuit
board.
1 Check the wiring between TB1 and
outdoor noise f lter circuit board
2 Check CN5 wiring.
3 Replace outdoor noise f lter circuit
board.
4 Replace outdoor power circuit board.
5 Replace outdoor controller circuit board.
1 Check the f eld facility for the power
supply.
2 Check earth wiring.
3 Check CN2 wiring.
4 Replace outdoor controller circuit board.
5 Replace outdoor power circuit board.
12 Check the f eld facility for the power
supply.
3 Correct the wiring (U.V.W phase) to
compressor. Refer to 10-9 (Outdoor
power circuit board).
4 Correct the wiring of reactor (ACL)
5 Replace outdoor power circuit board.
6 Replace Reactor (ACL).
7 Check CN2 wiring.
1 Correction of a model select
2 Replace outdoor power circuit board.
3 Replace outdoor controller circuit board.