Mitsubishi Electric MSZ-G09SV-E1 Service Manual page 52

D
Check of compressor
Start
E 'Check of compressor
winding' on page 48.
Is compressor normal?
Yes
F 'Check of compressor
operation time' on page
48. Does the compressor
operate continuously?
Yes
Ok
E
Check of compressor winding
Disconnect the connector between compressor and transistor module,
and measure resistance between the compressor terminals.
<<Measurement point>>
at 3 points
BLK-WHT
BLK-RED
WHT-RED
<<Judgment>>
1.88 to 2.31"(MUZ-G09SV)/ 0.39 to 0.50"(MUZ-G12SV)at -10:
to 40: of part temperature
0["] ···············abnormal [short]
Infinite["] ·······abnormal [open]
NOTE 1. Be sure to zero the ohmmeter before measurement.
2. Winding resistance for each phase is 2.14"(MUZ-G09SV)/
0.45"(MUZ-G12SV)at 20:.
F
Check of compressor operation time
Connect the compressor and activate the inverter. Then measure
the time until the inverter stops due to over current.
<<Operation method>>
Start heating or cooling operation by pressing the EMERGENCY
OPERATION switch on the indoor unit. (Test-run mode)
<<Measurement>>
Measure the time from the start of outdoor fan running till the
stop of the inverter due to over current.
<<Judgment>>
For reference
0~10 seconds·····················abnormal (short)
10~60 seconds···················abnormal (compressor lock-out)
60 seconds~5 minutes·······abnormal (refrigerant circuit defect)
more than 5 minutes···········normal
No
No
w Measure resistance between the
lead wires at 3 points.
Replace the compressor.
Is the compressor
operation time more than
10 seconds?
Yes
Check the refrigerant circuit.
Ohmmeter indication
"
X1
"
X1
"
X1
0 sec.
10 sec.
60 sec.
5 min.
52
No
Replace the compressor.
WHT
2
normal V
(1~several ")
Compressor motor
abnormal
(0" ····· short)
abnormal
(infinite····· open)
Outdoor fan starts
Abnormal
(Compressor winding short or layer short)
Abnormal
(Compressor lock-out)
Abnormal
(Refrigerant circuit defect, etc.)
Normal
RED BLK
3
1
W
U