FINE PRINT: The actions described here are most likely dangerous, so if you try to do this on your own, have fun!
The Situation:
I'm sitting here using my computer for important business tasks, and WHOOMP...it dies. My UPS is beeping, but
there is still power to everything in the room except a few devices. I look down and see a red light and a
yellow light blinking -- this is not a Good Thing.
After cursing a few times I tried turning my system back on...nothing. Tried turning the UPS off/on, got a beep or two
from the self test, but no power on the backed up outlets. This was definitely a Bad Thing.
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Needing to get some work done, I bypassed the dead outlets with a spare surge strip and powered back up. | Then when it was time to play, I took out the battery for testing (with the system still running as to not interrupt my Kazaa downloads yet again). | |
When I start to think, it gets crazy...
So now I have a UPS that is half dead. I figure the battery needs to be replaced since it's close to 4 years old now.
So where to get a battery for an older UPS? I couldn't find this model anywhere, and a new unit with the same short
run time would cost me over $100. This is when I remember seeing some larger batteries at
EPO (EPO Rocks!). I walked in, and there was a special on a 26Ah battery
for only 30 bucks. Mine was something like 8Ah, what a deal this was...until I went back to the battery section.
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This behemoth is what I ended up purchasing, all 51Ah of it, for only 50 bucks! It's big, it's bad, and it's RED (whatever that's worth). | I'm telling you this thing is massive -- here it is next to a 0.5L water bottle. It weighs over 40 pounds even! |  |
For those that care, here is a close-up of the label.
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When I got home I fitted some 14 AWG wiring with ring & blade connectors to properly attach the battery to my UPS. | Then I tested it to make sure it was done correctly, got a nice 12.5V reading here. |  |
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Next I hooked it up to the UPS, and then taped up the bit of exposed metal. | I then made a notch in the housing to pass the wire through, and put the unit back together. |  |
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I cannot stress the size of this beast enough...here it is next to my original battery. | This tape is not for safety so much as a deterrent. My cat, Porter, had already discovered these battery terminals make nice metal chew-toys. |  |
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Final Thoughts: So here it is, in the official installation spot, buried in the wire jungle behind my desk right next to the subwoofer and anti-cat styrofoam block. This this is probably going to take about a week to fully charge! But man, next time the power goes out here, I'm going to keep on computing for a LONG TIME. 03/03/2003 - Stay tuned for an update on how long this thing can run my energy-sucker without AC power. 06/27/2003 - UPDATE! After writing an email to somebody's inquiry on this & having it bounce, I now have some "free" content to put up here, so read on for more! |
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Some genius named Scooter who doesn't know his own email address writes:
On your hacks page, I saw a mod to a UPS. Does this still work?
I'm thinking about getting a bigger battery for my weak UPS. I was
wondering if you could tell me what specs on the two batteries should
match, and which one tells if it lasts longer. I appreciate you
taking some time to answer my questions, thank you very much.
The Response: Yes, it works (to an extent), and I still have it in use.
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Depending on your UPS, it might not charge a very large battery to 100%, and if it does it could take a LONG time. Also, your UPS inverter might not handle running for as long as the battery can. This is because most low-end UPS models have a tiny inverter, with a small solid block of aluminum for a heatsink, and it's all closed up inside the unit! |  |
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My UPS will overheat after running on battery for a while, at which point it just shuts down completely to avoid spontaneous combustion. I have run it with the inverter exposed & a 6" fan blowing on it (powered by the UPS itself!) and that gave me quite a bit more runtime before overheating. This was a very unsafe solution of course!
Also, you must only attach ONE battery to your UPS. The new battery should be rated for 12V, which most every UPS battery is. There are other things like float voltages and such, but you'll probably never find out what those ratings are for the factory battery. For this type of battery, they tend to be pretty close to one another, so it's not a major concern. The number that equates to capacity is the Ah (Amp-hours), more capacity = more runtime. So if you plan to do it, do it safely with proper connections and common sense. And if something melts and takes your house down with it, this never happened and I don't exist ;-) |
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Go back to Dr. Cheap's House of Hacks!
