How to Discharge a Capacitor ?

[slackmax]

It is a medium size capacitor on a fan motor inside an air handler. Can I simply short out the two terminals on it with a screwdriver? That's what they do on Youtube.

Short it out, then take the wires off, then remove it from air handler and test it.

I am kind of leery of sending voltage into the other components when shorting the capacitor.

Worrying needlessly ?

Is it any better to remove the capacitor first, then short it out?

[GilesMM]

I remove them first. Just be careful handling them.

[slackmax]

I remove them first. Just be careful handling them.

Thanks.

[ATtiny85]

Similar to gilesMM, I normally use an insulated pair of pliers to yank one terminal off.

I normally prefer to wait a fair amount of time (some hours) before hitting it with the screwdriver. The zap and sparks are not generally a problem, but still.

[slackmax]

Similar to gilesMM, I normally use an insulated pair of pliers to yank one terminal off.

I normally prefer to wait a fair amount of time (some hours) before hitting it with the screwdriver. The zap and sparks are not generally a problem, but still.

Did you mean yank one lead off?  Why just one? Sorry to be so dense.   

[the_fella]

You can buy capacitor discharge tools on Amazon.

[mre]

Yes, you are worrying needlessly.

Short with screwdriver and be done with it.  The capacitor stores energy and with the system turned off, if charged, the capacitor is the voltage source.  When you short it, the source is gone.  Sending voltage into other components is not a thing.

[phildonnia]

You wouldn't be "sending voltage" to other components.  If anything, you'd be removing voltage. 

Two insulated screwdrivers with an alligator-clipped wire connecting them.  <SNAP!> and you're good. 

If you can get the right angle, then you don't need the wire, just touch the screwdriver shafts together.  I used to "de-zap" televisions this way in my youth.

[BORN SAVER]

Same as a 9v you lick the positive and negative at the same time.

[lutorm]

Depending on the size of the capacitor, it might be more gentle to use a resistor than a hard short. But really, if you just wait a while it's very likely to already be discharged, all you're doing by shorting it is making sure.

[SmashYourSmartPhone]

Measure voltage on it first.  Many modern devices include a high resistance bleeder resistor to discharge capacitors over a matter of hours or days for safety.  If it's 0V or near enough, it's already drained, no reason to discharge it.

If it's bad, it's likely also not holding a charge.