I have an APC ES550. It’s been running fine for years. Recently I had to replace the battery, which was kind of annoying because that battery was only about 16 months old but it was only a one-year warranty. So I got a new battery. That one went out in about 4 days. So I replaced it from the same supplier and that one went out in about 3 days.
Went out = waking up to UPS chirping, replace battery light lit
So I either got two bad batteries in a row or the UPS is shot. How do I tell if the UPS is shot?
Try unplugging the ups from the wall, does it correctly fail over to battery power but only last for a short period or do the devices lose power?