BACK-UPS RS-900 Stays on battery and beeps

[BillP]

Sorry all if this has been covered in a previous thread - wasn't easy to search for this exact problem.

I have a RS-900 that recently switched to battery and stays there - regardless of good utility voltage. I checked the voltage sensitivity level and it's set to medium (factory default), but my voltage in the building is at 119V anyway. I tried to install the Powerchute software to see if there was any other diagnostic options in the software, but it keeps telling me it can't detect the UPS (even though I connected from my USB to the RJ45 data port). I use my USB ports frequently - have no known issues there.

Any troubleshooting tips on this UPS? Or is it most likely dead? It's probably 4-5 years old, batteries were replaced last year. I tried hard reboot including unplugging and re-plugging in the battery. The output circuit breaker is not tripped.

Thanks.

[BillP]

Jeremy,

Let us try adjusting the sensitivity of your UPS to low using the manual process. If you are using something like the BR900 UPS which has four LEDs you can open up this [BR900 User Manual|http://www.apcmedia.com/salestools/ASTE-6Z7V73_R0_EN.pdf] then go to page number 2 of the PDF.

With regards to your UPS being unable to detect, make sure that it is directly connected into a USB port on your PC and not on a USB hub. Next, open up Device Manager and let us know if it shows there.

[BillP]

Got it. Thanks. I don't know the harmonic content of my power source.

No other USB devices were plugged in at the time.

[BillP]

Thanks Jonathan. I have an RS-900. So I set the sensitivity to low, and that "fixed" the problem - it didn't immediately flip to battery. Again, my voltage is around 119V - no where near the low or middle limit to cause a switch to battery - that stays on battery. Still begs the question, what's wrong, and is it something I can fix easily? The manual states that "low" is not to be used for computer loads, which is what I'm backing up.

No, Device Manager does not see the UPS connected.

This UPS is probably 4-5 years old. Is that the expected life?

Thanks, Jeremy

[BillP]

Jeremy,

Though you are feeding an acceptable voltage into the UPS, one thing that could cause this is the frequency distortion also known as total harmonic distortion or dirty power. The UPS sees that you are feeding 119V AC but it also looks at the frequency, if it is too distorted the UPS would go to battery to provide good frequency.

With regards to the UPS being undetected by the PC, have you tried removing all the USB devices and just leave the UPS connected?

[BillP]

Jeremy,

From my experience, you would have to use an oscilloscope to view or see the distortion on your input. With regards to your USB, do you have any idea if those USB ports were version 2.0 or 3.0?

[BillP]

I believe USB 3.0. New computer, so that's most likely. Should I try it with a 5 year old computer?

[BillP]

If it is indeed USB 3.0, I would try using a much more older USB version. Here is the URL link on the customer that I helped before [http://forums.apc.com/spaces/11/netbotz-hardware-software/forums/general/7162/netbotz-450-temperatur...]

[BillP · Accepted solution]

Thanks - I'll give it a shot.