I purchased a Back-UPS 900 (BN900M) from a garage sale. I figured the battery was already dead. When I powered it on, the power button blinked green several times (self-test, I assume) and it started giving off a continuous beep. I figured that meant the battery was dead as I had expected.
I purchased a non-APC replacement battery from Amazon. When I installed it I got the same response when I turned on the UPS - blink, blink, blink... solid tone. I left it plugged in overnight but it didn't make a difference. Does this mean I got a bad or incompatible battery or is there something I can do to reset the dead battery flag and possibly get it working?
The battery is listed as "UPG # 40812 UB1290 12V 9Ah" with a title of "Universal Power Group 12V 9AH SLA Replacement Battery for APC Back-UPS 600 BN600"
Sorry to hear, unfortunately all I can do is recommend the official battery replacement for your unit which I believe is:
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