Mitsubishi Heavy Industries SRRM40HENG-L, Handbook, Page: 42 / 1106

40
SRK-GZ
(3) Inspection procedures corresponding to detail of trouble
[Broken thermistor wire,
connector poor connection]
Is connector connection good?
YES
YES
NO
NO
Replace PCB.
Correct connection.
Replace thermistor.
30
25
20
15
10
5
30 20 10 40 50 60 70 0 –10
Temperature (˚C) Resistance (k
Ω
) Temperature (˚C) Resistance (k
Ω
)
0 164 70 8.7
5 127 75 7.3
10 99 80 6.2
15 78 85 5.3
20 62 90 4.5
25 50 95 3.9
30 40 100 3.3
35 32 105 2.9
40 26 110 2.5
45 21 115 2.2
50 17 120 1.9
55 14 125 1.6
60 12 130 1.4
65 10 135 1.3
◆
Thermistor temperature characteristics
(Room temperature, indoor unit heat ex-
changer temperature, outdoor unit heat
exchanger temperature, external tem-
perature)
◆
Discharge pipe (Comp. dome) thermistor temperature char-
acteristics
Temperature (˚C)
(Shortcircuit)
(Broken wire)
Resistance (k
Ω
)
Current cut
[Open phase on compressor output
terminal, compressor lock]
YES
YES
NO
NO
YES
NO
¡
Check compressor wiring visually.
¡
Check insulation resistance. (1 M
Ω
or over)
¡
Check coil wire resistance. (Few
Ω
)
Does current cut operate when
operating inverter with compressor
wire disconnected?
Is output voltage applied to all 3
phases of power transistor?
Is there any shortcircuit?
Inspect compressor.
Defective inverter
Defective inverter
Secure space for suction
and blow out.
If check results are normal,
compressor is locked.
Is thermistor resistance value good?
Thermistor error