How To Check Inverter/ Compressor; Check Of Open Phase; Check Of Transistor Module - Mitsubishi Electric MSZ-G09SV Service Manual

MSZ-G09SV - MSZ-G12SV -
E1
MSZ-G09SV - MSZ-G12SV -
E2
When OPERATION INDICATOR lamp flashes 5-time.
Outdoor unit does not operate.

How to check inverter/ compressor

A
Disconnect the connector
between compressor and
transistor module.
Check the voltage
between terminals.
No
Are voltages
balanced?
Yes
Check the
compressor.

Check of open phase

B
Be sure to use the analog voltmeter for measurement.
With the connector between compressor and transistor module
disconnected, activate the inverter and measure the balance of
voltage between terminals.
Operation
Model
mode
COOL
MSZ-G09SV
HEAT
COOL
MSZ-G12SV
HEAT
<< Operation method>>
Start heating operation by pressing the EMERGENCY OPERATION switch
on the indoor unit. (test-run mode)
<<Measurement point>>
at 3 points
BLK-WHT
BLK-RED
WHT-RED
<<Judgment>>
Balanced································Normal
Unbalanced···························Abnomal (open phase)
Shutdown by overcurrent·······Abnormal (short)
NOTE 1. Measure AC voltage, at 3 points more than one minute after the
outdoor fan motor starts running.
2. The output voltage values in above table have tolerance withinJ i20%.

Check of transistor module

C
Disconnect the connector between compressor and transistor
module, and measure resistance between terminals on the
transistor module.
<<Measurement point>>
at 6 points
BLK-WHT, WHT-BLK
BLK-RED, RED-BLK
WHT-RED, RED-WHT
<<Judgment>>
Infinite ["]···········Normal
0~dozens of ······Abnormal (short)
MUZ-G09SV -
E1
MUZ-G09SV -
E2
See B "Check of open phase" on page 76.
Check the resistance of transistor module.
See D "Check of compressor" on page 77.
Operational
frequency
[Hz]
79
58
85
58
w Measure AC voltage between
the lead wires at 3 points.
w Measure resistance between
the lead wires at 3 points
MUZ-G12SV -
E1
MUZ-G12SV -
E2
See C 'Check of transistor module' on page 76.
Is resistance
infinite?
Output
voltage
[V]
190
BLK-WHT
155
190
ACV
155
BLK-WHT
ACV
76
E1
on page 76 ~
E2
A
Yes
Replace the outdoor
electronic control P.C.
board.
No
"
(0~several )
Replace the transistor
module.
Voltmeter indication
BLK-RED WHT-RED
ACV ACV
300 300 300
BLK-RED WHT-RED
ACV ACV
300 300 300
ohmmeter indication
"
Normal
(infinite)
X1
"
Abnormal
X1 (0~dozens of ")
on page 83
Q
Normal
(Balanced)
Abnormal
(unbalanced)