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Power supply input discharge voltage

  1. Jan 20, 2010 #1
    I would appreciate any help, opinions or explanations on this as I am receiveing many different views currently.

    I measure the discharge voltage of a single power supply (laptop ac charger) using a digital chart recorder. On a trial and error basis I achieve the data as close as possible to the mains cycle peak.

    The results show that the live to neutral charge drops to 100v at 117.8mS and is fully discharged at 900mS

    I then plug 16 identical power supplies into a single power strip and in turn in to a single socket.

    The results show that the live to neutral charge drops to 100v at 500mS and is fully discharged at 3000mS.

    The problem is that I have a graph showing the above test results, but I have been told by two seperate electrical engineers that when the power supplies are connected in parrallel to a single power supply, physics dictates that the discharge should be constant and the time to discharge should be identical.

    If anyone can shed any light on the above, either for or against their argument I would be extremely grateful.

  2. jcsd
  3. Jan 20, 2010 #2
    What is the input resistance of your chart recorder? Perhaps it forms a significant part of the discharge path when only one power supply is connected, shortening the discharge time.
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