Question about my UPS

[bardos]

I bought a second hand UPS on ebay a while back, the seller saying there was a new battery installed... I've been noticing through testing (and blackouts) that it will last me only about one minute before shutting down.

It's an Eaton Ellipse eco 800 which uses by default one 12v 9AH battery. So I opened the case today to see what was happening... Basically I have a couple of 12v 7AH batteries sitting around and was thinking the guy had probably lied about there being a new battery in the UPS. I was thinking to replace the "bad" battery with a good one, but of lesser AH.

To my surprise, the battery inside *was* a 12v 7AH battery. It gave a 13v readout on my multimeter. Seemed good.

Anyway, I was wondering if this is the reason that the battery will only last one minute and if I throw a 9AH battery in there to fix it, the problem will end. Or what?

Any help with this conundrum appreciated. Thanks

 

[jefferysummers]

UPS are generally designed to allow time to shut down your PC when there is shortage of power and they are not designed for the continual use of your system. Only most cheap units will allow contin ual power of 1 minute.

 

[TheGardenTool]

The Eco 650 uses a 7AH battery and is only rated for 400 watts. Like you mentioned, the Eco 800 uses a 9AH and has a 500 watt rating. So it's 25% increase in rated wattage for using the correct battery size for the unit. I imagine you are nearing the entire 400 watt capacity for the battery to only last ~1 minute as it is. You would get more runtime with the right AH battery but it likely won't be much.