Page 105 - Testing Electronic Components

An Insulation Tester
When I connect the filter capacitor to the meter and press the ready

button-it showed a very low resistance and this proved that a short circuit
occurred between the plates when high voltage applied! A good filter
capacitor will just showed a charge and discharge in the insulation tester
just like when you are testing a capacitor using analogue meter. This
proved that the bad capacitor breakdown when under full operating
voltage.

You can get an insulation tester from any electronic suppliers. It comes in
few ranges of 100v, 250v, 500v, 1000v and even 5000 volt! If you want
testing capacitor of 220 microfarad 400 volt then you have to select 250
volt. If you select 500 volt, it will blow your capacitor that is under test
because the voltage you have selected is higher than 400 volt! If possible,
you should get exact value and voltage for capacitor replacement.

Capacitor breakdown when under full voltage is quite rare and only
happen to those capacitor that have 250 volts and above. If you come
across some tough dog repair and could not locate the fault in the
electronic board, I’m sure you will know what meter to use now. Go find
the culprit.

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