Capacitor Testing

*This is the same procedure for checking and air conditioner, refrigerator, washing machine capacitor as well*

With the microwave unplugged, use a metal (not the shiny chrome type) screw driver with a insulated handle to short across (touch both at the same time) the terminals of the high voltage capacitor to discharge it.

This is a common way to do this....

capacitor

If the wire terminals and wires are coated ( not bare metal) you can use a pair of needle nose pliers with insulated handles to short/discharge across the capacitor.

Set your needle meter to an OHM scale, Example: Rx1

meter

Touch your leads together and 0 ( zero ) out your meter with the adjustment wheel.

With wires off of the capacitor ( write down where they go first! )...touch the cap terminals ( red lead on left and black lead on right )...the needle should move away from the infinity ( probably left side ) and move slightly ( towards the right side ) and go back to infinity...reverse leads and ( red lead on right side and black lead on the left side ) on the cap and the needle should move away from infinity even further and then go back to infinity = a good cap. ( note - some caps have a built in resistor that you may read ).

good

If the meter needle goes all the way over to the right side and stays there = a shorted capacitor. ( refresh page will start the animate picture again)

shorted

Just refresh this page if the needle meters above stop working.

Microwave Repair and Maintenance Parts


Related Links

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  2. Microwave Capacitor Parts
  3. Microwave Switch Parts
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