(4) Simple checking procedure for individual components of main inverter circui
✻
Before checking, cut the power off and remove the required parts from the control box.
t
Part name
Judgement method
Diode stack
IPM
(Intelligent power module)
Rush current protection resistor
R11, R12
Electromagnetic contactor
(52C1, 52C2, 52F)
Refer to "Determining diode stack troubleshooting" (
9
.[4].7.(6) )
Refer to "Determining IPM interference" (
9
.[4].7.(5) )
Measure the resistance between terminals: 47
Ω
±
10%
(1) Zero to several ohm, or Meg failure.
(1) Main power breaker trip
(2) No remote control display
(1) Operates normally without tripping the
main breaker.
(2) Main power breaker trip
Check item
Phenomena
Treatment
Perform Meg check between the
terminals in the power terminal
block TB1.
Turn on the power again and
check once more.
Turn on the outdoor unit and check
that it operates normally.
Check each part in the main inverter circuit.
• Refer to "Simple checking Procedure for in-
dividual components of main inverter circuit".
a. Diode Stack
b. IPM
c. Rush current protection resistor
d. Electromagnetic relay
e. DC reactor
f. Noise filter
a. There is a possibility that the wiring shorted
momentarily.
Trace the short and repair.
b. If a. above is not the case, there is a possi-
bility that there was a compressor failure.
• A compressor ground fault can be consid-
ered. Go to (2) - [2].
(3) Trouble measures when main power breaker tripped
[1]
[2]
[3]
Current sensor
ACCT
Disconnect the CNCT2 target connector
and check the resistance between
terminals: 280
Ω
±
30
Ω
1-2PIN (U-phase)
3-4PIN (W-phase)
U
U
V
IPM
W
ACCT-W
W
ACCT-U
DC reactor DCL
Measure the resistance between terminals: 1
Ω
or lower (almost 0
Ω
)
Measure the resistance between terminals and the chassis :
∞
❉
Check the ACCT connecting phase and direction.
A1-A2
0.1k~2.0k
Ω
L1-T1
L2-T2
L3-T3
13-14
31-32
L1-T1
L2-T2
L3-T3
13-14
31-32
∞
∞
13
L1
L3
L2
A1
A2
31
14
T1
T3
T2
32
Checking position
Judgement value
Pushbutton
Pushbutton
[In the case of 52C1, 52C2]
[In the case of 52F]
13
L1
L3
L2
A1
A2
14
T1
T3
T2
Button
ON
(pushdown)
Button
OFF
1
Ω
or less (Almost 0
Ω
)
1
Ω
or less (Almost 0
Ω
)
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