Back-UPS ES 750 doesn't work with replacement batteries

[Anonymous user]

In 2008 I got a UPS Back-UPS ES 750 and it worked great until a few months ago.  I noticed that the battery wouldn't charge past 35%, and after emailing support they told me that the battery needed to be replaced.

I replaced it with a Werker battery at a local store which charged to 100% and passed a load test.

A week later that batter would no longer change past 35%.

I took it back to the store and exchanged it.  They tested it and said it was dead.

The new battery wouldn't even power on the unit.  It would just beep whenever I turned it on.  I took that battery and the unit back to the store to show them.  After getting ready to buy another unit, the guy there tried one more time to turn on the unit and it worked.  I brought it back home and it charged to 100%.

A week later it won't charge past 53%.

I emailed support and they said that I shouldn't have used a non-APC battery.

So does this sound like I got another bad battery?  Is my UPS going bad?

[Anonymous user]

In 2008 I got a UPS Back-UPS ES 750 and it worked great until a few months ago.  I noticed that the battery wouldn't charge past 35%, and after emailing support they told me that the battery needed to be replaced.

I replaced it with a Werker battery at a local store which charged to 100% and passed a load test.

A week later that batter would no longer change past 35%.

I took it back to the store and exchanged it.  They tested it and said it was dead.

The new battery wouldn't even power on the unit.  It would just beep whenever I turned it on.  I took that battery and the unit back to the store to show them.  After getting ready to buy another unit, the guy there tried one more time to turn on the unit and it worked.  I brought it back home and it charged to 100%.

A week later it won't charge past 53%.

I emailed support and they said that I shouldn't have used a non-APC battery.

So does this sound like I got another bad battery?  Is my UPS going bad?

[Anonymous user]

Now the battery is below 50%.

[BillP]

I am not sure how a battery could do this on its own but what happens if you pull the plug while watching the PowerChute status? I wonder if it re-adjusts somehow (beware your computer may turn off too - not sure if that is an option)..

[BillP]

good morning,

to me, it sounds like a potential failed battery charger in the UPS itself based in the charge percentage behavior. Are you using PowerChute? Sometimes the UPS is able to report an internal fault for situations like this? I know you're able to see the battery charge so I wasn't sure how you're reading that?

Also, with third party batteries, let me clarify that. Users can use third party batteries if they want - we'll only void a warranty if we find the the third party battery damaged the UPS which would void any remaining warranty. For instance, if the third party battery leaked all over the UPS and damaged it, we wouldn't necessarily cover it because it was not an APC battery.

For what you're doing though and what you're seeing, a third party battery vs. APC branded one should not be a concern here and I'd disagree with it being related to the problem.

Considering you've now tried multiple batteries, it seems safe to say that it is likely the UPS causing a problem and like I said, seems to be the battery charger failing based on the symptom. I'd see if you can return the battery and look towards a new UPS or trading in your current UPS via our Trade UPS program.

(If you're interested in trade in - there is some info here -> Recycling Options - recycle). It's OK if the UPS is no longer functioning.

[Anonymous user]

Hi Angela,

Thanks for the reply.  Yes I am using PowerChute.  I will see if I can get a new UPS since I have tried two batteries on this one, although the first battery I tried was confirmed as being bad by the store that sold it to me (Batteries Plus).  This one went from 100% to under 50% in a few days.

Thanks.

[Anonymous user]

FWIW, I'm having the same problem with my ES 750, which is why I'm here now. I had been using a 3rd party battery for a couple of years without any problems. It started failing and I replaced it with another non-APC battery. The new battery charged to 100% and started dropping a few days later. I eventually got another non-APC battery—this time guaranteed fresh from a reliable battery supplier—and it's failing in the exact same way. After all that, I guess I need a new UPS. Oh well.

[Anonymous user · Accepted solution]

Checking around the web, this seems to be a frequent problem with the ES 750, Many people report the same thing, usually after replacing the battery because the old one seemed to have failed, and even if the replacement was an official APC battery. Clearly there is something that fails in the ES 750 design, most likely the battery charging circuitry, after a few years of use. I've seen it suggested that an electrolytic capacitor dries out and stops the charging circuit from working. I would pursue this further but haven't been able to find a schematic for the ES 750 circuit board.

Typically the failing units are out of warranty (no surprise.) I still think APC has some responsibility to look into this and provide answers, since the problem is fairly common. I note that several similar threads appear here, and all of them end up without being resolved. Disappointing response on APC/Schneider's part.

I have one of these units as well. It performed correctly for the first three years, but when a battery replacement was required, it did the same thing everyone else reports: failed to keep the new battery charged properly and seemed to actually drain the battery any time the UPS is turned on. I checked this by putting my battery on an external SLA charger for a day, which brought it back up to 13.5 V output. Sure enough, putting it back into the ES 750 and leaving the unit turned on (even with no load) for 24 hours drained the batter back to 53% charge according to PowerChute. Clearly this is a design defect or a defective component in the UPS itself. My unit is an older one at this point, but still BE750G on the label.

[Remarkable]

I opened mine up after I confirmed battery was good, and UPS worked powering stuff until battery depleted, but wouldn't recharge.

There was one capacitor that had bulged - replaced that, and charging circuit functions again.

Not going to post pictures or locations of the cap, as the circuit will change, and yours will not look like mine. If you can't figure out what to do from the above description, just retire the unit and get a new one.