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Can somebody show me a circuit to charge a 16volt 10,000uf Capacitor bank in a relatively short time? Answered

Hi, i have a bank of 16V 10,000uf capacitors that im using to make a battery tab welder.  The problem i have is charging them.  Can somebody show a capacitor charger circuit that can charge these caps in a reletively short time....  60 seconds at the most.  I tried using a camera circuit but the thing to 30 minutes and 37 seconds to charge the capacitors...... i counted....  please help me. 

Thank-You.

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steveastrouk (author)2010-10-19

How MANY 10,000uf caps ?

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user

200,000uF

A 1 A PSU, 16 V with a 16 Ohm resistor will charge in 3 seconds ish.

Steve

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user

Can you post a schematic?

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user

Use a laptop charger, and 16 Ohm resistor. Job done.
I AM assuming you are only charging to 16-18V ?

Steve

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user

what does the rating on the laptop charge need to be? or does it even matter?

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user

Doesn't make a lot of difference, just use a resistor.

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user

is it the same resistor no matter what? and what should the resistors wattage be?

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user

For a 1A charging rate, on the laptop supply, its the same resistor. It could do with being at least 10W rated.

Steve

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Re-design (author)steveastrouk2010-10-20

See, I told you someone would do the math for you.

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Re-design (author)2010-10-19

You just need a 16 volt transformer with a diode bridge charging the caps. thru a 100 ohm or so resistor.

I can't calculate how many amps the transformer and bridge should carry or how many watts the resistor should be rated.  Someone will be able to calculate it for you.  I just don't do math like this very often and would have to look it up.  Or you could look it up.

The resistor is there because when the bank is empty it will look like a short circuit to the bridge and you need to have some resistance there.

The reason the camera charger takes so long is because it is having to create 16 volts out of 1.5 or 3 and that takes a while plus your bank if very much larger than what it was designed to charge.  I'm very much surprised that it lasted a whole hour.

You just need to start with more power and step it DOWN instead of up.

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silencekilla (author)Re-design2010-10-20

is there an instructable on here that shows how to make a step down capacitor charger? if so can you post a link?

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orksecurity (author)silencekilla2010-10-20

Have you looked at the existing instructables on coilguns and the like?

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seandogue (author)2010-10-20

Are the caps rated for fast charge discharge? If not, charging them too fast will result in their early demise.

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