Self-test turns output power off

[Anonymous user]

Hello!

We have 2 Smart-UPS 3000RM's with AP9618 management cards. Systems are set up so that every 2 weeks they make a self test. Last month one of the UPS's started to cause trouble. It initiated self-test, but then it triggers a output power off because of an overload. That UPS has load of 16.9% only. Here's the log:

14.07.2013	13:18:36	UPS: Passed a self-test.
14.07.2013	13:18:21	UPS: The output power is now turned on.
14.07.2013	13:18:21	UPS: The load no longer exceeds 100% of rated capacity.
14.07.2013	13:18:20	UPS: Started a self-test.
14.07.2013	12:56:12	UPS: The output power is turned off due to an overload.
14.07.2013	12:56:09	UPS: A low battery condition no longer exists.
14.07.2013	12:56:09	UPS: The load exceeds 100% of rated capacity.
14.07.2013	12:56:07	UPS: The battery power is too low to continue to support the load; the UPS will shut down if input power does not return to normal soon.
14.07.2013	12:56:02	UPS: Started a self-test.

The UPS won't turn on output power unless I remove 2 plugged in cords. After that I can turn UPS on, it starts and I can plug in removed cords. What might have caused this kind of problem and what can I do to fix it?

[BillP · Accepted solution]

How old are the batteries in this system? It also could be a "battery overload" type situation for when the UPS is transferring to battery power during the self test. When I first read this, my first thought is an old faulty battery causing this type of behavior but I wanted to check with you on the age of this installed battery.

Also, not sure if you're able to, but do you see the same behavior if you manually transfer the UPS to battery too? (like pull the plug from the wall on the UPS or trip the upstream breaker?)

[Anonymous user]

I will test this out during weekend.

Batterys are from when we purchased UPSs. So couple years at least. But UPS itself has not yet requested new ones

[BillP]

Yeah what I am saying this might be the UPSs way of requesting it. Depending on how the battery is failing internally (since it has chemicals, plates, etc) it might not be having an issue with voltage drop while applied with a load (which is what the self test does) but it could be failing when load is applied to it in a different way (overloading the inverter or similar).

[Anonymous user]

You were right! The cause is dead battery's.