Smart-UPS 2200 non-APC battery problem

[Anonymous user]

Hello, all. Sorry if this is a bit long winded, but I really, really want to get this working. I spent a lot of time and gas and money getting this UPS.

I recently got my hands on a Smart-UPS 2200 with bad batteries. I took it home and promptly removed the connectors from the old batteries (after trying them in the UPS to no effect) and wired them to two Werker 12 volt 44 amp hour batteries. I know these batteries are good, as I have been cycling them on an older 600 VA APC UPS.

I plugged it in and pressed the "power/test" button. It powered up, and seemed to come on. Then it beeped a few times and the "Replace Battery" light came on. I powered it off, unplugged it, plugged it back in, and powered it up again. It did the same thing, the "Replace Battery" light came on. I pressed the "power/test" button and it seemed to go into the test mode, and all lights turned off except the bottom most "Battery Charge" light. I figured it was either doing it's test, or it was charging the batteries. So I watched it for a minute or two, then left.

I came back about 20 minutes later and saw that the bottom most "Battery Charge" light was still on. I pressed "power/test" button and the UPS turned on. The "On Line" light came on, the fan came on, and it seemed to be OK. I watched it for a couple minutes, and everything seemed good, so I left. After probably 20 minutes I heard a high pitched noise coming from where the UPS is. I raced down there, thinking it was some alarm, but when I got there I could tell it wasn't. The noise was coming from inside the UPS, and wasn't an alarm. I quickly unplugged the UPS and the noise slowly faded. I put a hand on the top of one of the batteries and it was hot, I put my hand on the side of the other battery and it was very, very hot. I could hear the water inside the batteries sizzling. I quickly unplugged the connectors from inside the UPS and checked the voltage on the batteries. One read 13.5 and the other 13.7.

So, my question is this: why did the UPS do that to the batteries? I wired the connectors exactly like the originals. The only differences between the originals and my new ones is that the originals were actually two packs of two six volt batteries, each pack wired in series to make 12 volts. My batteries would be the same 12 volts, but with a higher amp hour rating. This should work, but it didn't, and I don't know why.

Any help would be hugely appreciated. I wanted to use this for my file server, hardware firewall, and networking stuff, and it's a quite disappointing that it doesn't work.