Checks
SiBE04-101
122
Service Diagnosis
5.1.6
Power Transistor Check
(Capacitor Voltage Check)
Check No.14
1. Power transistor check
Note:
Check to make sure that the voltage between the terminal of Power transistor (+) and (-) is approx. 0 volt
before checking power transistor.
< Measuring method >
Disconnect the compressor harness connector from the outdoor unit PCB.
Follow the procedure below to measure resistance between power transistor (+) and (-) and the U, V and
W terminals of the compressor connector with a multi-tester. Evaluate the measurement results for a pass/
fail judgment.
<Power transistor check>
<Measuring positions>
2. Capacitor voltage check
< Measuring method >
Before measuring, operate the unit for several minutes, then shut down the operation by force using the
circuit breaker.
If the unit is shut down using the remote controller instead of the circuit breaker, the capacitor
discharges the electric load, thus disallowing accurate measurement.
Note:
The charge section is applied with high voltage. Therefore, exercise caution during measurement to
prevent electric shock.
Negative (-) terminal of
tester (positive terminal (+)
for digital tester)
DC + 130
UVW
DC - 130
UVW
Positive (+) terminal of
tester (negative terminal (-)
for digital tester)
UVW
DC + 130
UVW
DC - 130
Normal resistance
Several k
Ω
to several M
Ω
(
∗
)
Unacceptable resistance
Short (0
Ω
) or open
1P059375J
U
DC+130
V
W
DC-130
SiBE04-101.book Page 122 Monday, October 15, 2001 3:08 PM
