Specifications

Check SiBE04-624
204 Service Diagnosis
3.4 Power Supply Waveform Check
Check No.8 Check the voltage waveform between power supply terminals on the terminal board for
disturbance using oscillo-tester.
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Check to see if the power supply waveform is a sine wave (Fig.1).
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Check to see if there is waveform disturbance near the zero cross (sections circled in Fig.2)
3.5 Capacitor Voltage Check
Check No.10 Before this checking, be sure to check the main circuit for short-circuit (Check No 29).
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Checking the capacitor voltage
z
With the circuit breaker still on, measure the voltage according to the drawing of the model in
question. Be careful never to touch any live parts.
[Fig.1] [Fig.2]
DB1
LED A
LED5
S90
Thermistor
lead wire
S70
Fan motor
lead wire
S80
Four way valve
lead wire
S20
Electronic
expansion
valve coil
Multi meter
(DC. voltage
range)
(R6027)