Mitsubishi Electric PUZ-ZM60VHA2, Service Manual

Page: 43 / 140

43
OCH771
Check Code Abnormal points and detection method Cause Judgment and action
U9
(4220)
Detailed
codes
To find out the detail history (latest) about U9 error, turn ON SW2-1, 2-2 and 2-6.
Refer to "10-9. FUNCTION OF SWITCHES, CONNECTORS AND JUMPERS".
01
Overvoltage error
• Increase in DC bus voltage to
ZM60-140V: 430 V
ZM100-250Y: 760 V
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
Check the field facility for the power supply.
2
Correct the wiring (U.V.W phase) to
compressor. Refer to "10-8. TEST POINT
DIAGRAM" (Outdoor power circuit board).
3
Replace outdoor power circuit board.
4
Check compressor for electrical insula
tion. Replace compressor.
02
Undervoltage error
• Instantaneous decrease in DC
bus voltage to
ZM60–140V: 200 V
ZM100-250Y: 400 V
1
Decrease in power source voltage,
instantaneous stop.
2
Disconnection or loose connection
of CN52C on the outdoor power
circuit board/controller circuit board
(ZM100–140V)
3
Defective converter drive circuit
in outdoor power circuit board
(ZM60–140V)
4
Defective 52C drive circuit in outdoor
power circuit board
5
Defective outdoor converter circuit
board (ZM100–140Y)
6
Disconnection or loose connection
of rush current protect resistor RS
(ZM100–250Y)
7
Defective rush current protect
resistor RS (ZM100–250Y)
8
Disconnection or loose connection
of CN2 on the outdoor power circuit
board /controller circuit board
(ZM60–140V)
9
Power circuit failure on DC supply for
18V DC output on outdoor controller
circuit board (ZM60–140V)
1
Check the field facility for the power supply.
2
Check CN52C wiring. (ZM100–140V)
3
Replace outdoor power circuit board.
(ZM60–140V)
4
Replace outdoor power circuit board.
5
Replace outdoor converter circuit board.
(ZM100–140Y)
6
Check RS wiring. (ZM100–250Y)
7
Replace RS. (ZM100–250Y)
8
Check CN2 wiring. (ZM100–250Y)
9
Replace outdoor controller circuit board.
(ZM60–140V)
04
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
than or equal to 6A.
1
L1-phase open (ZM100–250Y)
2
Disconnection or loose connection
between TB1 and outdoor noise filter
circuit board (ZM100–250Y)
3
Disconnection or loose connection
of CN5 on the outdoor power circuit
board/CNCT on the outdoor noise filter
board (ZM100–250Y)
4
Defective ACCT (AC current trans)
on the outdoor noise filter circuit
board (ZM100–250Y)
5
Defective input current detection
circuit in outdoor power circuit board
6
Defective outdoor controller circuit
board
1
Check the field facility for the power
supply. (ZM100–250Y)
2
Check the wiring between TB1 and out
door noise filter circuit board. (ZM100–
250Y)
3
Check CN5/CNCT wiring. (ZM100–250Y)
4
Replace outdoor noise filter circuit board.
(ZM100–250Y)
5
Replace outdoor power circuit board.
6
Replace outdoor controller circuit board.
08
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
more is detected on power
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 synchronous signal
circuit in outdoor controller circuit
board
5
Defective power synchronous signal
circuit in outdoor power circuit board
1
Check the field 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.
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