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FRIDGE
11-03-2005, 05:14 PM
hi guys, im doing a college assignment and i need to know how to test a start capacitor with an ohm meter, help would be well appreciated, thanks! ;)

chillyhamster
11-03-2005, 07:50 PM
Using a low voltage multi meter, connect probes to each tag, meter should register full deflection and then slowly fall back to 0. If meter fails to register or stays at full deflection then cap is suspect and should be tested on a proper capacitor tester. You can also use a megger to carry out test but be sure to discharge before handling.

chemi-cool
11-03-2005, 08:42 PM
Hello FRIDGE,

The best way to test a capacitor is by using a capacitor tester.

http://www.azpartsmaster.com/shopazp/Capacitor+Tester+(MM2700).html

Capish?

Chemi :)

Argus
11-03-2005, 11:57 PM
Most Meters these days are digital and do not lend themselves to testing capacitors. Neither do small analogue meters. So it?s best to use a capacitor tester. As electronics exercise you can make one yourself.
If you have access to an old fashioned AVO that had a resistance scale using 15v output, you could see a gradual change on the scale when connected across the terminals as Chilly describes, but generally you need a greater voltage output for the bigger start capacitors on things like compressors.

If there is a dead short or if the scale shows open circuit, then sling it out.

These methods do not tell you the rate of charge or static retention. You will need proper equipment for that.

Finally, I would not advise a megger as the output voltage is usually higher than the working voltage of the capacitor. An Electrostatic capacitor can generate enough heat to split it open when exposed to a full crank on a megger.
(I know we've all done it, but it can be dangerous).

Hope this helps.
________
herbalaire vaporizer (http://herbalairevaporizer.com)

Temprite
12-03-2005, 12:55 PM
hi guys, im doing a college assignment and i need to know how to test a start capacitor with an ohm meter, help would be well appreciated, thanks! ;)

Put an active and neutral across the capacitor and discharge it on the neck of the nearest person.If they yelp capacitor is ok. :eek: :D

FRIDGE
12-03-2005, 05:58 PM
thanks a lot guys. your help is well appreciated ;)