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APC UPS on steroids (bigger batteries)

Today I got a used APC UPS RS 1000, you know those things that should keep your system up and running when the power fails.
The batteries where toasted, this happens to all these devices after about a year.
Since new batteries only last a year and cost about $ 65 and can only keep your system up for a very short time I decided to hack something together.
I got some brand new car batteries and hooked them up, (yes I included a fuse for safety)
You might ask: "Do you really need a UPS in the Netherlands?"  Answer, "no, not really" but it is fun to have and since the UPS was free I now have some long lasting power.
Here are some pictures. This is just a sort of useless nerdy fun.

Power! the lights come on right away.

OK, maybe 16 square mm wire is too much?

General setup, 2 batteries and the UPS.

And another picture.

I will test the performance and add data later, I will leave this stuff loading the batteries for a few days.


Unknown zei…
Hi! And how did the batteries performed? Are they still alive now? :)
#oetelx zei…
Today I had to replace one of the batteries.
One is still OK, the other was high impedance and the UPS was beeping.
There was no way to revive the bad battery, had to buy a new one.
It lasted about 3.5 years, seems longer than the original batteries.
Jeff zei…
I did the same thing as you except i hooked up 24-AGM Trojan batteries.
The batteries finally failed 9 years later. So now I installed 17Ah batteries because soon i intend to install 105Ah Lithium iron phosphate batteries.
I received my APC second hand. it is a 220Volt outlet.
Now, lets see just how long the APC will last...

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