Page 103 - Testing Electronic Components
P. 103
Testing Capacitors That Breakdown When
Under Full Operating Voltage
Testing capacitor breakdown when under full load or voltage only can be
done by using special meter. Normal digital capacitance meter and
analogue meter cant test this type of failure. Have you encountered
power problem where when you switch on the power supply, the fuse
blow immediately? You have measured all the components in the power
(primary) and secondary area and all the components seem to be
working! Where is the culprit?
A fuse blown into dark colour were usually caused by lightning strike, a
shorted bridge rectifier, defective Posistor in computer monitor and TV
circuit, a shorted power transistor or FET field effect transistor, shorted
primary winding in switch mode power transformer, shorted secondary
output diode and etc.
A Filter Capacitor in Switch Mode Power Supply
Im frustrated as to where be the cause of the power problem. Every time
when I switch on the monitor the fuse will blow immediately (the fuse
became dark colour and this indicates that there is a major short circuit in
the power supply section or surrounding area which Ive already
mentioned above). I have tested all the components in the power supply
section and can't find the cause of the problem. Then, I began to
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