Re: Question for our electrical engineers

John Bigboote wrote:
Should devices with capacitors be stored with the capacitors charged
or discharged? I'd always assumed the latter, since I figured that
voltage will leak from one side of the capacitor to the other over
time (if I understand how they work at all). But I've heard it's
better to store them charged.

These are in monoblock photo lights (big-ass, A/C-powered photo flash
units), FWIW.

Thanks,

-jb

I built a power supply for some computer test equipment in the late 70's. Big power transformer that supplied various voltages in the 12 to 45 volt range (all center-tapped). I got some big full-wave bridge rectifiers and some big caps - in the range of 25K to 60K microfarads. Each cap had a bleeder resistor on it to take down the charge in a controlled fashion. These caps stored enough charge to kill you, and could supply enough current momentarily to do serious damage to the metal in a screwdriver.

--Steve
.

Relevant Pages

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