APC Back-UPS NS (1250) Loud Hissing

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  • Welch
    New Member
    • Dec 2011
    • 9

    #1

    APC Back-UPS NS (1250) Loud Hissing

    So as I posted on my intro to the forums, I'm a computer tech. And as a tech I come across LOTS of used/damaged items being given to me. In the past month I've had to replace 3 APC Back-UPS NS 1250's. They have all served well over there 3-4 year life span and these models aren't made anymore. Usually the batteries get to a point where they have to be "Reconditioned" or replaced. As of late, the batteries cost nearly as much as the units brand new!

    I figured out of 3 units, I should be able to figure out how to fix them and Frankenstein them together. 2 of them hiss very loudly when plugged in. 2 of them have batteries I'm sure don't hold much if any charge... 1 of them I believe has a decent battery. Sort of hard to tell whether the batteries are the issue or if its because the charging unit is defective, perhaps some of the internals that are apart of the charging system are causing the high pitched hiss I hear (electrical trickle).

    Before I just abandon them and throw them away, I figured it would be fun to try and salvage them. Anyone work on similar units or a UPS before? My other project is an Antec PSU... I've got not experience with items like this that could potentially kill me, so figuring how to drain the larger caps is some information I was hoping to be taught.
  • Scenic
    o.O
    • Sep 2007
    • 2642
    • Germany

    #2
    Re: APC Back-UPS NS (1250) Loud Hissing

    Youtube user Maxxarcade (who's also on this forum btw) has had success recapping an APC UPS on which the charging went wonky.

    As far as i can remember, he replaced almost all caps on the main/controller board (probably excluding the mains filter grain silos)

    Comment

    • severach
      Badcaps Legend
      • Aug 2007
      • 1055
      • USA

      #3
      Re: APC Back-UPS NS (1250) Loud Hissing

      Batteries in series don't charge right when unequal. To test the batteries you hook them up in parallel and charge with a standard battery charger. Batteries that get warm, won't charge up to full voltage, or won't hold a charge for a few days should be marked for recycling.
      sig files are for morons

      Comment

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