Bought a replacement battery for my computer's UPS. Put it in there a week ago. Yesterday, flipped the fuse to work on an outlet and the battery lasted three minutes and then shut off. What??
Reached out to support. "You do realize that UPS is 17 years old, right?" Oh. Hm.
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Open it up (carefully) and check for obviously bad electrolytic capacitors
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I like the way you think!
I drained the battery using a technique from a site I found on the Internet Archive (seriously) and now charging it back up to see if it'll reset the mechanism the UPS uses to calibrate charge duration. Hesitant to believe it'll work.
Next: capacitors!
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