Modifying a UPS backup for use with a Deep Cycle 12v battery.

[ThePCGuy]

That is what I plan on doing with an old APC 350VA backup that I received with a dead internal battery. I thought about just leaving the unit as is and hooking up an external battery, but I changed my mind (for the time being) and will most likely be using a large project box for everything which will then be attatched to a marine battery box. The plan for this is to be a standalone power system for camping trips. It will be powering small items such as lights, chargers, etc. I've also thought of adding outside battery terminals so I can connect it to my car battery for use while driving. Eitherway, has anyone here played with anything like this? I figure I'll work up a few plans in the next week and then start on getting everything setup. Oh, and the onboard warning speaker to let you know that the 120v power source has failed will be removed. No Beep beep beep. Also, in order to charge the battery, I'm going to include

http://thepcguy.myvnc.com/jim/apc.jpg
http://thepcguy.myvnc.com/jim/apc2.jpg
http://thepcguy.myvnc.com/jim/apc3.jpg

- Jim

[bchur83]

As long as the internal battery and the Deep Cycle battery are the same voltage, I dont see why it wouldnt work. Just remember you are still limited by the 350VA handling capacity, so you will only be able to power smaller items, but the battery should last quite a while.

[Adragontattoo]

It WILL work BUT the UPS will not put out more then its rated power no matter the number or size of batteries you add.

The circuitry in the UPS is the limiter there.

Im not saying to not do it but I would suggest doing it on a much larger UPS to equalize the cost to benefit.

[ThePCGuy]

I'm not looking for more power out of the unit, just more battery time. For the little things that I run on it, it should run most everything. No hairdryers, etc. :).

- Jim

[Adragontattoo]

then it is totally feasible!

FYI charge the battery before installing it, the load of charging that gigantor battery can do some havoc on the UPS otherwise.

[ThePCGuy]

Yes, the new battery will definently be charged on a separate circuit. I was thinking of buying one of those tiny 1amp trickle chargers to keep it ready to go until I need it. Should work a-ok.

- Jim