Technology
Capacitor Discharge in Action

cap_discharge.jpg

Note: Some makers have commented that this particular project should not be attempted unless you know exactly what you are doing and have taken the right precautions.

bbum’s found a cool way to get a photo with lots of sparks:

* Take a part a disposable camera, desolder the capacitor and rig up a charging circuit.
* Charge the capacitor
* Turn off the lights
* Set your digital camera on a 5 second exposure*
* Use a bit of metal to discharge capacitor at the focal point of the camera
* Upload photo to flickr

‘Cause splosions are cool – Link

14 thoughts on “Capacitor Discharge in Action

  1. Will this work with any capacitor? Obviously, spark size will vary, but to get the effect in this photo, do you need to use high voltage or high capacitance (which are inversely related, if I’ve learned ANYTHING in physics class…)?

  2. nice shot. Amusing how they mention protecting the lens of your camera, but no mention of safety glasses. Gloves would be a good idea, too.
    For samurai1200, the *energy* in a capacitor given by
    1/2 C*v^2
    more energy = bigger spark.
    so a big cap with a high voltage is your best bet, and also the most dangerous.(or fun)

  3. I’m not having a dig at anyone but this Make is pretty reckless. It should at least be stated on the Make site that there is a real risk of injury playing with these caps when charged. I’d hate to see a young or inexperienced Maker get hurt.

  4. gang – it’s just a photo, it’s not a directive to do it, really. but on every page on make we have the following:

    Please Note

    Technology, the laws, and limitations imposed by manufacturers and content owners are constantly changing. Thus, some of the projects described may not work, may be inconsistent with current laws or user agreements, or may damage or adversely affect some equipment.

    Your safety is your own responsibility, including proper use of equipment and safety gear, and determining whether you have adequate skill and experience. Power tools, electricity, and other resources used for these projects are dangerous, unless used properly and with adequate precautions, including safety gear. Some illustrative photos do not depict safety precautions or equipment, in order to show the project steps more clearly. These projects are not intended for use by children.

    Use of the instructions and suggestions in MAKE is at your own risk. O’Reilly Media, Inc., disclaims all responsibility for any resulting damage, injury, or expense. It is your responsibility to make sure that your activities comply with applicable laws, including copyright.

    Always check the page associated with each project before you get started. There may be important updates or corrections.

    ==

    be good.

  5. The photo is really quite a bit more dramatic (and cool looking) than reality.

    It is a low voltage electrolytic capacitor.

    Ben and I have been zapped quite a few times. Scares the snot out of you and might leave a little bit of a burn mark. Tiny. But it doesn’t really hurt that bad — frankly, there is more danger of hurting something while flailing around in response.

    As you can see in the original photo (http://www.flickr.com/photos/bbum/436602164/ — I like this crop better), quite a few sparks are bouncing off Ben’s hand. They don’t hurt. Can’t even really feel ’em.

    Glasses? Yes. Wear ’em. Always a good idea.

    Gloves? Probably a good idea, but not a lifesaver.

    Open containers of gasoline on the work surface? Nope. Bad idea.

  6. Cool effect! The sparks really look dramatic with the long exposure like that.

    My 2 cents about the dangers of caps: when I was making my guitar tube amp (remmelt.com/amp) the danger of the caps was very real. These are 16uF, 450V caps, loaded with just over 460V DC. That is serious stuff, you can really get hurt on a cap like that. You can also die when touching the wrong wires. Caps have the capacity to push a lot of charge through whatever it’s hooked up to in a short time, and if it’s hooked up to YOU, you’re in for a ride.

    Just saying, be cool, be reckless, be safe.

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I'm a tinkerer and finally reached the point where I fix more things than I break. When I'm not tinkering, I'm probably editing a book for Maker Media.

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