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Thread: Hazard due to power supply capacitor

  1. #1
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    Hazard due to power supply capacitor

    Hey people,

    if you consider a circuit diagram like the full wave bridge power supply shown on this page:

    http://www.plitron.com/pages/technote.htm

    when I built this circuit I used a 30,000uF capacitor at 80V.

    Okay, so suppose the power supply is turned on, and then switched off. The capacitor gets charged at some lethal amount, and gets connected to a gecko drive. I've been debugging the gecko which has a plug connector. I've been carefully slipping off the connector and discharging across the caps with a pair of plyers.

    Well, I dunno, I guess once the whole system is debugged then maybe it wont really matter if the caps are charged up. But there will always be a gazillion joules waiting across the terminals of my power supply. What I'd like to avoid is leaving a lethal dose in those capacitors. Think of it as protection for my cats.

    Owen
    Attached Thumbnails Attached Thumbnails Hazard due to power supply capacitor-105_0570.jpg  


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    Last edited by sendkeys; 09-06-2004 at 04:53 PM.


  3. #3
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    1) The drives discharge the capacitor within a second of you turning off the AC power.
    2) There are 96 Joules stored at 80VDC (J = C * V^2 / 2) but the voltage is too low to do more than tickle a little bit.

    Mariss


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