Sunday, November 15, 2009

Continous loud tone on a Sunday morning

"wow, my ears are ringing badly today", I thought while making coffee for breakfast this morning. And it wouldn't get better, so I started to look around whether that very high-pitched continuous sound came from outside. Nope. I looked in the garage. Yep, definitely louder, so it's not my ears. It's not the furnace. It's not in the train room, but it gets louder when I go to my work bench and side door. It's not my neighbor either.

Finally, I tracked it down to the UPS of the communications cabinet, an APC BackUPS ES 450. The power LED was blinking between green and red, and unit was clearly emitting the sound. I pressed the power button to shut it down and the noise stopped. Phew. Turned it back on, and the beep came back immediately. Screw it. I turned it off again, plugged the various transformers into the non-UPS sockets. Everything came back up just fine.

After breakfast and being properly caffinated, I looked at the support pages at and sure enough they have a FAQ entry describing my exact problems. Battery self-check failed.

The Back-UPS ES performs an internal self-test every 14 days, the internal self-test checks the integrity of the battery. If the battery fails the self-test, the Power on LED will flash and the unit will emit a constant tone.
A self test should be performed with the UPS fully charged (charging without interruption or transfer to battery for 5 hours) and normal load attached. To do this, power down all equipment attached to the battery outlets. Then reboot the Back-UPS ES by turning it off then count to 5 and power it back on. If the constant tone clears, then it was a false onbattery condition and the unit has been reset. It now is ready to be used again.

Hmmm, so this unit performs an automatic self-test every 14 days, and it *may* fail the test, even though there is nothing wrong with it. The solution is to turn everything off, reset the unit and turn it back on. How lame.

"Legendary reliability" be damned, I know what I'm not going to buy again.

No comments: