I had the HT UPS fail this past weekend. This is an APC unit with filtering, surge, AVR and pure sine wave UPS. These list for $1400+ and sell for about $800. The silver units were discontuned a couple years ago and I grabbed one when they were blown out at $299. Cool thing about the unit is with our LED back-lit LCD TV we can get close to 1 1/2 hours of TV wathcing off this thing if the power goes out.
Anyway, power went out Saturday for a few seconds and the unit didnt kick in. Went to alarm status saying "Inverter Overload" contact APC. If the unit sits off for a while, it will pass self test and seems to work fine. But unplug power and it wont go into battery back up and gives the same fault warning. If it's been running and warm, it wont pass self test on reboot and goes right to the "inverter overload" fault display. With battery removed, it works fine but gives flashing no battery warning (obviously).
2 year warranty and it's under warranty still but contacting APC, I can tell they dont want to deal with it although they have to under warranty and will. The "tech" stated that it is almost always the battery when that fault condition flashes. The batteries are 7 years old as the unit was built in 2005 and Im sure they didnt replace batteries at the close-out prices. They are sending me a replacement battery pack.
The question is ... does this sound right? I would think that an inverter overload warning would indicate a problem on the inverter output, not the battery input side. The unit also is equipped with a replace battery and/or low battery warning or other battery faults and none of those are showing up. I would think that would show up if it were the batteries. By the way, this is a 48 volt system (4 x 12 volt 7AH batteries in series). Battery voltage measures 52+ volts as would be expected. I realize that voltage doesnt tell the whole story about battery conditions. But again, Im skeptical that the fault is with the batteries and/or the input side of the inverter. And no, the output isnt overloaded, it does the same with no load or a lamp connected.
Any thoughts or insights appreciated.
Thanks