Question about APC Back-UPS 400VA (BK400) UPS System

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APC back UPS 400 fails to give back up

I have 3 year old APC back UPS 400 i changed the old batteries and put new batteries 6 months back. now when my power goes off my ups doesnot give back up and my system goes off as soon as there is power cut. what is the problem

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Re: APC back UPS 400 fails to give back up

I have the same problem with an apc smart-ups VS 650.


New batteries - charge in batteries is good (also tested under load).


When AC power fails, no power is supplied to PC connectors by the UPS.


UPS self test works fine. UPS does not report any problems via software - Power Management under Windows XP.

Posted on Oct 16, 2007

Re: APC back UPS 400 fails to give back up

Dear fixya...i'm using Pioneer UPS 500..I'm not able to get backup even after changing my old battery...but after changing my battery...I've chaned the adjustments of presets which are of 10K...tell me how to do the adjustments in correct manner

sandeep deol

Posted on Nov 01, 2008

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Re: APC back UPS 400 fails to give back up

I think u have problem with u r battery...

may be not working properly..

change u r battery and then try again...



dont forget to tell me u r problem solved or not

best regards & best of luck..

even u can mail me at my mailing add-

Posted on Oct 13, 2007

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