blinking battery light on back ups 1500

[Anonymous user]

inherited a 2 yo lightly used APC back ups 1500, battery light blinking, not used in a year, displays no error code, safe to assume it just needs a long charge up?  Manual is a bit vague but assuming it has just been unplugged too long and trickle drained? 

[BillP · Accepted solution]

Yes, you can try letting it charge up. Anytime a UPS is stored, you should disconnect the battery and periodically charge it around every six months.

I'll assume this is the replace battery LED flashing (versus on battery)? This means the UPS thinks the battery is disconnected which if it is not charged and has a low voltage, it could appear "missing" or disconnected.

So, it is worth letting it try to charge in the UPS for a day or so but if it doesn't go away, the battery may be damaged and unable to hold a charge. You could also measure the DC voltage on the battery if you have a voltmeter.

Depending how that turns out, rarely this can be a fault where the UPS mistakenly reports that but I doubt it for how the battery and UPS hasn't been in use for a while. Once you let it charge, you could test the unit's operation by removing AC power/pulling the plug to see if the UPS transfers to battery and supports the load or if it cannot and possibly turns itself off too.