Help me get the right diode

Discussion in 'The Projects Forum' started by MFDK, Jul 4, 2015.

  1. MFDK

    Thread Starter New Member

    Jul 4, 2015
    Greetings everyone!
    I'm working with a conversion project here on some old server power supplies. (aware of high voltage risks)
    A fairly simple mod to turn them from their normal service in (old outdated) servers, to able connect them in series, deliver and matching up power for RC battery charger equipment.

    The basics of the conversion tells to remove and isolate the DC ground internal from the metal case in one supply, while leaving DC ground intact in the other. This with two reasons of making the power supplies work correctly together in series, but keeping as well important safety functions.

    Then it is required place two diodes across each output as protection, in cases current should be flowing in the wrong direction into one of power supplies. This could be scenarios when the two power supplies doesn't turns on at the very same moment or if only one supply shuts down due to over current protection (OCP) or of other reasons.

    Each power supply can deliver about 50A 12V, before the over current protection kicks in.

    The attached png illustrate the wiring, but there are absolutely no info to find on the diode.

    My question: What do you guys think would be suitable here?
  2. AnalogKid

    Distinguished Member

    Aug 1, 2013
    The diode might have to carry significant current. To be safe, you want a diode rated for at least 60 A and 25 V. A Shottkey diode would be better than a standard power diode, but will cost more.

  3. MFDK

    Thread Starter New Member

    Jul 4, 2015
    Seem clear enough for me to get forward. Thanks.

    If anyone have other or better suggestions, they are welcome. Thanks for looking!
  4. Bordodynov

    Active Member

    May 20, 2015
    Digi-Key $2.97