Re: [CAD_CAM_EDM_DRO] Capacitor safety questions

volitan712003 wrote:

>Hello,
>
>I just ordered a 12,000uF x 100V capacitor for my power supply. I know
>capacitors can be deadly but I have no concept of what a micro farad
>is. If this cap is fully charged, is this thing big enough to kill?
>
>

At 100 V, if your fingers were wet or had cuts, and you jammed them onto
the terminals, yes, it could be fatal. This would be a pretty unusual
event.
But, that's why people put bleeder resistors on them, so they discharge in
a short amount of time.

>Another question is how can I check it so I know it's discharged. I'm
>guessing it would have too much power to hook my volt meter up
>directly.
>
>

Huh? Have you ever hooked a voltmeter to the power line to check the
line voltage? The power mains have a capability to deliver several thousand
amps into a short until the breakers trip. But, a voltmeter is a
high-resistance
device, and does not draw much current. Assuming your voltmeter has a
range above 100 V, set it to that range and you can read the voltage
directly.
Be careful not to short the capacitor with the voltmeter probes. It
will make
a noise like a gun going off, and then you'll need new probes.

Jon