Announcement

Collapse
No announcement yet.

UPS shorts out

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    UPS shorts out

    My dad got two free UPS from work, one works fine the other doesn't. It trips its internal breaker as soon as I plug it in. I see nothing wrong with the board, can't find anything wrong. My dad plugged it in with the board disconnected, and it didn't trip. when he plugged the transformer into the board it blows. Not sure if its a problem with the transformer or something on the board. Any help would be great.
    Btw the caps are nichicon
    Attached Files

    #2
    Re: UPS shorts out

    looks like a best power.
    look to a welded relay or bad mov's.
    those units work well with an external deep cycle battery too.

    Comment


      #3
      Re: UPS shorts out

      how do you test if the mov's are bad, I know they're the red epoxy coated things.
      so the relay should be closed not open

      Comment


        #4
        Re: UPS shorts out

        Desolder the MOVs and measure the resistance between them. If you get readings near zero ohms, they are shorted and need to be replaced with units of the same type.
        My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.

        Comment


          #5
          Re: UPS shorts out

          thank you Mr. Ham and Japlytic, because I hate to have to pitch it if its just a bad relay or mov. I did a continuity test and none made it beep, but it might be different with more voltage.

          Comment


            #6
            Re: UPS shorts out

            pull the mov's and try again.
            that relay looks odd in the pic.

            Comment


              #7
              Re: UPS shorts out

              Dust cap on relay can be popped off for closer look.
              Board itself looks like it may have been wet?
              Jim

              Comment


                #8
                Re: UPS shorts out

                I don't think it has ever been wet, and the relay still moves.
                Put a piece of paper between the contacts, pugged it in and it didn't blow, so its definitely something on the board and most likly an mov

                Comment


                  #9
                  Re: UPS fixed, not really

                  I fixed it!!! : : :


                  wasn't worth fixin' because both batteries are bad
                  Attached Files

                  Comment


                    #10
                    Re: UPS shorts out

                    Did you try the batteries from the good unit in it first?

                    If they do work, and the other batteries are bad, you can usually get SLA batteries (typically used in alarm systems) of the same phsical dimensions and voltage for it.

                    If the unit has two batteries in series, fully charge each 12V battery individually before installing them in the UPS.
                    My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.

                    Comment


                      #11
                      Re: UPS shorts out

                      bad batteries not a big deal.
                      https://www.badcaps.net/forum/showthread.php?t=1579
                      thats what i do with all the free dead battery ups's i get.
                      and i never have a problem selling them.

                      Comment


                        #12
                        Re: UPS shorts out

                        My Dad checked the batteries, he tried a car battery charger and they still wouldn't come up past 7 volts each. It is still good for parts and stuff
                        It was refurbished in 03 but the case was made in 94. RIP 06

                        Comment


                          #13
                          Re: UPS shorts out

                          As said earlier, if the battieries are the only problem you can get it up and running for close to nothing...
                          "The one who says it cannot be done should never interrupt the one who is doing it."

                          Comment


                            #14
                            Re: UPS shorts out

                            It was refurbished in 03
                            3 years is about right for replacement of batteries. i guess they changed them then.
                            capacitor lab yachtmati techmati

                            Comment

                            Working...
                            X