Battery capacity falls down to 3% after a self test

[BillP]

Hello,

I have a SUA3000R2IX322, which is installed since Dec 2010.

I remember that, after one month of usage, I was forced to ask a battery replacemente because of a very similar problem, and after the substitution took place there were no further problems.

Today, contextually with the self test, which is scheduled every 14 days, the battery capacity suddenly dropped down to 3%, and now, after more than three hours it's charging again and going back to 100% as if it was charging a discharged battery.

Which could be the reason if this and which actions should be necessary ?

Under this UPS it's running a small virtualization system and the load is always around 18%. The last complete discharge of the battery happen around 1 year ago.

Thank you for a feedback!

[BillP]

This sounds like a battery that is "on its way out" and failing.

Batteries should be lasting 3-5 years typically but several factors can affect that number such as environment, quality, usage, etc.

Were the replacements genuine APC batteries? If it was replaced under warranty, they should be.

I'd also check on the temperature where the UPS is installed to see if it is well ventilated and cool to lengthen the lifespan.

Do you have a lot of outages?

[BillP]

The replacement was done under warranty and the room is cold enough: the internal temperature of the ups is reported by the status page as 19.8 celsius.

Normally outages are not a problem: I remember only two big outages since the ups installation.

But sometimes (sometimes once a week, other times it happens more times for a short period) I see that the log reports an outage of two or three seconds. Due to the fact that the ups is placed in a remote site, and these outages happen mostly in early morning, I can't directly verify if these reported short outages are really power supply defaults or not.

[BillP]

Hmm. Yes, that temperature aligns with what is located in the knowledge base (What is the expected life of my APC UPS battery? | FAQs | Schneider Electric US), assuming ambient temperature is the about the same.

It has been almost about 3 years though since the last replacement so maybe everything is in order and it is just time for new batteries. The UPS will most likely completely fail the self test shortly after nothing the 3% capacity after the self test.

[BillP]

I'm sorry, but I made a mistake in the first post!

The installation took place in Dec 2011, not in 2010. In fact there was in my mind the certainty that the ups didn't reach two years of life, and your words about three years sounded strange to me....

[BillP · Accepted solution]

OK, I understand

I see no reason based on what we've discussed so far that this is not a battery issue (versus UPS problem) but I know the puzzling part is why did your batteries not last longer.  I can only outline the issues that I know cause it unfortunately but it is feasible a combination of all of them at some point contributed to early failure. It also possibly these had an issue from when they were manufactured considering they are made up of plates, chemicals, etc.