# Question About Wiring a Capacitor

• George Young
In summary, using a switch will allow you to charge the capacitor and then release the energy when you activate another switch. This is similar to how a camera flash works.

#### George Young

TL;DR Summary
basic capacitor question
EDIT: I looked this up and I don't think you can do what I originally thought of. Instead, you can use switches. Not that complicated. I'd delete the thread but they don't usually like to let you do that. I just asked because I don't know much about capacitors and I thought I might learn something. My charge/release circuit has two loops and three switches.

Original Question: Can I have a capacitor that is charged with the battery when you activate one switch and that releases the capacitor energy when you activate the other?

In other words, there are two circuits - one for the battery to charge the capacitor and one for the capacitor to release its energy to a coil of wire.

Are there capacitors that work like this or will I need to build my circuits some other way?

Last edited:
Sure. Switch 1 connects the capacitor to the battery. Switch 2 connects the capacitor to the coil. First close 1 and open 2, then open 1 and close 2. Can you draw the circuit diagram for that?

George Young
George Young said:
Summary: basic capacitor question

Original Question: Can I have a capacitor that is charged with the battery when you activate one switch and that releases the capacitor energy when you activate the other?
Better yet, use one SPDT Form-C (break before make) switch...

http://www.ni.com/product-documentation/4453/en/

George Young
You could also put a big enough resistor between the battery and the capacitor so that you don't have to disconnect the battery. Then you only need one switch, and you don't need to worry about the timing of opening and closing the switches. Of course this will slow down the charging, but maybe that's OK. This is basically how a camera flash works. On many of the flash units, you can hear the capacitor re-charging after you fire the flash.

George Young