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Capacitor bank charger question. Answered

I know alot of people use a standard disposable camera's circuit board as a charger for coil guns, but would this be sufficient for a bank of ~20 of those capacitors?
If not, what would I use to charge it?
They are 330v 80uF capacitors, by the way.
EDIT: Or would there be a way to modify the existing charger circuit to charge the larger amount of capacitors?



8 years ago

im pree sure if u take the diode out of the camara circut the transformer output would be ac and then you could probs put it throught a voltage mulitiplyer

Jack A Lopez

8 years ago

Presumably a bank of 20 capacitors would take 20 times as much time to charge up than just 1 capacitor. I mean this is based on the assumption that the little camera flash-charger circuit is only capable of so much power.

Energy, the stuff you're putting into the capacitors, is the time integral of power. If you want more capacitors to charge in the same amount of time, then you want proportionally more power supplied by your charging circuit.

There's no easy way to modify a cheap little camera charge to make it produce 20 times as much power as it did before.

This suggests that you want a new power supply.

Perhaps you could feed 120 VAC into a voltage doubler, to give you 2*21/2*120 = 339 V.  This is assuming you live in the Former U.S. or some country that uses 120 VAC for the mains power.  Actually if you live in Europe, you don't even need a doubler, just a simple bridge rectifier and a capacitor  will do.

You might also want some sort of current limiting resistor, so it won't trip the breakers off when you turn it on.

And you know, double check your math, and be safe and stuff.