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i need desperate help with this transformer for a capacitor charger? Answered

okay.. heres the dealio. I DON'T KNOW HOW TO USE THIS BLOODY THING!
okay, i have this to charge about 15-20 200v 470uF capacitors and the multimeter i have has a capacitance option but idk how to hook the capacitors at the same time to even charge them right and be able to immediately fire the coil gun when they are full.. so basically i need to figure out how to hook this transformer to about 15-20 capacitors, charge them all simultaneously, then when they are charged, fire the coil gun.

50/60Hz 8.2A 900W

this is a computer UPS by : ULTRA

the 2 batteries are 12V 28W



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Best Answer 9 years ago

Capacitors need DC voltage not AC. The transformer puts out AC,. So you must convert the AC to DC. This is done using diodes or a bridge rectifier (4 diodes inside a small square box). What you are trying to do is a somewhat ADVANCED project. If you are new to electronics, you might want to start with something less dangerous and less advanced so you don't get hurt or discouraged if you fail.


Answer 9 years ago

so is this AC to DC converter a thing i can make? i also have a thing you plug into a cigarette lighter in a car that will convert to 120v AC. can i alter that to make this thing work to charge my capacitors?

if not, can i use a computer power supply to charge my capacitors? i only want the capacitors to be charged in order to fire a coil gun.

so what can this transformer be used for? if it can will it sell on ebay, how do i even know if it still works?

Jack A Lopez
Jack A Lopez

9 years ago

From reading this question I get the impression that you know very little about how to build a coil gun, and very little about electricity in general.

And I think that is the reason people have been reluctant to answer this question is because they do not want to have to explain everything about everything to you.  That's just a guess.

But as a consolation, I want you to know  you are  not alone in your ignorance.  People post to this forum all the time with the question, "How do I build a coil gun?", and also with specifics about how they have such-and-such hardware they think might be useful, capacitors, etc.  The question is of course, 'How to put it all together', right?

I wish I could just link you to one of the many lucid and well written instructables on the subject of coil guns,
but I haven't really seen any that are actually lucid and well written.  Maybe that means I should write one, but that would definitely be a lot of work for me to do.

It's not clear what to do with that big transformer you've got there.  Transformers like that one change AC (alternating current) from one voltage level to another, e.g. 120 VAC to 12VAC, or vice-versa.  For the purposes of charging a capacitor bank you want DC (direct current).  The usual trick to convert AC into DC is to use rectifier circuit, like the one shown here:
and this picture:

The other links I am going to give you are to a few of those occasions I can recall when I tried to answer this question before:

This one includes a circuit diagram I drew, and some hints on charging and discharging capacitors.

This one contains links to some capacitor-charging circuits drawn by someone else.


Answer 9 years ago

sorry for the VERY late reply, but i have gotten a transformer from a microwave and i have successfully made a coil gun and i am now working on a rail gun, i need better capacitors tho. your reply is not the answer to the question i asked, my own fault i overlooked the fact that this is an AC transformer, that is why i was clueless as how to hook it up to charge capacitors.

Next time please answer someones question, not go on and on about everything else other than what they are wanting to know, you wont get rep or best answers this way


Answer 8 years ago

You "over looked the fact that this is an AC transformer"?
Somehow I highly doubt you've completed a coil gun and are making a rail gun considering you think there are other transformers than AC transformers.... 'Jack a Lopez' provided you with educated answer that scared you into your ego.
Put down the high voltage electronics and educate yourself before you touch the wrong wire and end up 6 feet under.