[TriLUG] OT: Diagnosing APC Back-UPS Misbehavior

Pete Soper pete at soper.us
Tue Mar 19 11:16:33 EDT 2013


Thanks for the update. It would be fun to try to back track the "on 
battery" state back to the root cause of why it thinks it should be in 
that state and try to discover how on earth that relates to the 
batteries, or else what it is that died in both units to cause this 
failure mode.

On the other hand, much as it would be the case with APC, spending much 
time on this is like throwing money away unless the APC engineers are 
poised to mail out a cash reward for their job being done for them. :-) 
But if this failure mode isn't a complete fluke it seems likely APC 
would know about it in painful detail by now and want as close to zero 
PR about it as possible. You might try reading them the riot act, how 
you spent good money on batteries that can't be used properly, etc, and 
see if they'll improve their offer.

I'm sitting next to a pile of charger circuits and a UPS with its guts 
exposed and I could easily do a load test, but I think we should agree 
that your battery having a capacity problem and this relating to a 
spurious "on battery" condition would be extra-double weird! That is to 
say, I don't think you should spend one second on that avenue.

Two thoughts:
    1) Have you tried swapping an old  battery from one of the working 
UPS into one of the two giving the spurious "on battery" condition?
    2) What about moving a new battery into the "currently working" UPS 
involved with experiment (1)?

This might be able to vindicate the two units acting up while pointing 
the finger at a battery-type dependency in the APC design (maybe AGM vs 
non-AGM?).

-Pete


On 03/19/2013 07:57 AM, Scott Chilcote wrote:
> Hi LUGgers,
>
> For those who are curious, I've performed more tests and swapped emails
> with APC tech support on this problem.  Just as a reminder, these units
> are not reporting that the new batteries are bad.  They are instead
> reporting that the AC power is bad.  When they power up they switch to
> the "On Battery" state and start beeping x4, which is what they do when
> the power goes out.  There is no problem with the house power.  I
> measured it, and four other UPSes agree that it's up to snuff.
>
> Another data point.  I used a class 2 SLA charger to charge up the two
> new batteries.  They were nearly fully charged already, after sitting in
> the UPS(es) for several hours.  The charge light went green after a few
> minutes on both of them.  I don't have the equipment to rigorously load
> test these batteries, but there isn't enough evidence to demonstrate
> that they aren't good.  If someone has a way to do that, I'll give it a try.
>
> APC is being highly nuanced in their responses.  They aren't outright
> saying that the two UPSes are bad, but they did say that they do not
> recommend returning the batteries.  They are instead offering a discount
> program on replacement UPSes.  This seems generous for UPSes that are as
> old as these, and it makes me wonder if there might be something afoot
> with these UPSes.
>
> Another TriLUGger emailed me to say that he had had the same problem
> with a pair of the same model, so we're up to four BackUps XS 800s
> (bx800s) that are doing this.  My google searching did not turn up a
> huge number of similar complaints on this model, but we could be leading
> the wave.
>
> Thanks for all of the good advice.
>
>      Scott C.
>
>
> On 03/06/2013 03:49 PM, Scott Chilcote wrote:
>> Hi Folks,
>>
>> Sorry to wander OT, but I've seen good advice on this list related
>> to UPS problems and I'm hoping someone has some insight.
>>
>> I have two APC Back-UPS XS 800 units that I took offline last year when
>> they showed the "Replace Battery" light.  I ordered new batteries last
>> week, and put them in one of the units.  It did not come back to life as
>> expected.  It showed the "On Battery" light instead, and started beeping
>> four times.  This is what they do when the power goes off.
>>
>> I tried resetting the unit (disconnecting the battery and the AC plug,
>> holding down the "On" switch for 60 seconds).  No change.
>>
>> Then I tried setting the unit's sensitivity to the lowest setting.  This
>> caused it to power up normally (green light).  However, it soon started
>> making a relay chattering sound, which is quite loud.  I shut it off.
>>
>> Since I had another Back-UPS XS 800 that needed batteries, I moved the
>> batteries over to that unit.  I even changed out the cable and spacer
>> for the battery pair.  When I plugged it in - lo and behold - I had the
>> identical misbehavior.  Same "On Battery" state.  Same relay chatter
>> with the sensitivity set to low.
>>
>> Next step: Read the manual.  It says to check the AC voltage level in
>> the house.  I tried the UPS on several different outlets around the
>> house, same problem.  I measured the AC voltage, and got 113VAC on my
>> meter.  We have four other UPSes of varying kinds, and they are working
>> fine at the default sensitivity level.  The manual also says to
>> check the circuit breaker on the back of the unit.  I did that
>> earlier and found that neither one had tripped.
>>
>> I checked the voltage on both of the new batteries (disconnected).  They
>> make the meter swing to at least 12 VDC.
>>
>> These UPSes were both made in late 2004 according to their serial
>> numbers.  Did they die at the same time, while unplugged?  Do they count
>> the number of battery replacements and self destruct (humor)?
>>
>> I spent some time looking at APC's forums, this does not appear to be a
>> frequent problem.  I tried their online support chat, but the trees
>> outside my window were visibly growing while I waited (both of their
>> level ones may be off this week).
>>
>> Thanks for any cluefulness!
>>
>>      Scott C.
>>
>




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