My UPS ES 550 started ticking like a clock about 15 minutes ago. No lights, beeps, sirens, etc. All of the devices attached are working. The green power light is not on nor is the red "replace battery" light.
Model# from the sticker on the bottom is BE550G; S/N is 3B0823X36737.
That serial number indicates the device was manufactured in 2008! APC indicates batteries will normally last between 3 to 5 years, and devices should be replaced every 7.
It is well past time to use the APC TradeUPS program and get a new BE600M1.
I replaced the battery. I might have replaced it once since I bought it, so I have no complaints about how long they have lasted. I'll check out the tradeup program.
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