Check; How To Check; Power Transistor Check; Capacitor Voltage Check - Daikin FTK25JVE9 Service Manual

Si04-115

6. Check

6.1

How to Check

6.1.1

Power transistor check

Capacitor voltage check

Check No.3 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. To disengage the
connector, press the protrusion on the connector.
Then, 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>
Negative (-) terminal of
tester (positive terminal
(+) for digital tester)
Positive (+) terminal of
tester (negative terminal
(-) for digital tester)
Normal resistance
Unacceptable resistance
<Measuring positions>
MULTIMETER
(DC, VOLTAGA RANGE)
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.
"
Note: The charge section is applied with high voltage. Therefore, exercise caution during
measurement to prevent electric shock.
Service Diagnosis
Power transistor
TRM1
S90 THERMISTOR LEAD WIRE
COMPRESSOR LEAD WIRE
If the unit is shut down using the remote controller instead of the circuit breaker, the
capacitor discharges the electric load,
UVW
(+)
UVW Power transistor
(+)
Several kΩ to several MΩ (∗)
Short (0 Ω) or open
DB1
S80 FOUR WAY VALVE LEAD WIRE (RX TYPE ONLY)
thus disallowing accurate measurement.
Power transistor UVW
(-)
UVW Power transistor
(-)
S70 FAN MOTOR LEAD WIRE
REACTOR LEAD WIRE

Check

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