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Request: An Internal UPS or battery for a PC Answered

My town has been experiencing power dips and short outages. i bought a cheap ups but it doesn't really do the job (the PC still cuts out) but i noticed that my laptop carries on just fine (obviously because it has an internal battery) so that got me wondering. Inside the pc it's just 12v and 5v isn't it? surely you could set up a battery inside the case that works just like the one in a laptop. anyone fancy giving it a go?



10 years ago

You could wire together a a few Lithium Ion batteries, use the PSU to charge them, and add an inverter in there somewhere. It wouldn't be hard to make it so that you don't need the inverter, you could probably make a circuit to detect outage and switch the power to batteries for less than an inverter, splice it into the ATX cables or something.

Actually using an inverter is the more inefficient way of powering it because you are converting 12-24VDC into 120-230VAC to be yet again converted into 12,5,1.5,-12 and -5VDC so it is quite inefficient :)

thats what i need, essentially the way a laptop works but for a normal pc, i must point out that i am a bit of a novice, but i can follow an instructable, as long as there aren't any big words! (joke). seeing as you know more than me could you help me out by writing an instructable?

When I make some money and can afford the parts, I'll do it. Right now my bank account is in the negative, but maybe next month or so.

Awesome! That would be great! Cheers!

Computers need a multitude of voltages such as 1.5v for the CPU, -5 & -12v for the other things an all the other stuff. You probably wont be able to supply the current either because some 12v lines in a computer can handle a maximum of 20A!!!! and the 5v line is something like 10A!!!! p.s XBOX's also take 10A at times!!!!

here is one possibel way to run a system off a battery: there is a much simpler but less efficient methode. i you like, i could post it.


sorry, just thought of something, i am in the UK we run on 230v AC does that make a difference? and thanks for the diagram, but to me that might as well be written in arabic. i regognise the plug and thats about it. cheers anyway though.

well thats okay; the float charger simply needs to be set to run off 220 volts. i found a simple way to run this system though. ill post it soon (i have swimming lessons now)

. Unless you can build a charger/inverter yourself, the best bet is to buy a UPS. They are dirt cheap nowadays (I've seen 500W units for 30-40 $US) and available just about everywhere that sells computers or accessories. From my experience, the "overgrown power strip" models are all but worthless - good for occasional short blips, but very little run time (ie, won't get you through an outage). . If you just need enough time to shut down the computer in an orderly manner, you don't need a big UPS. One rated to run your load (don't forget the monitor, speakers, printer, &c; that will be turned on at the time) for 10 minutes should work. . You will not get the extended run-time of a laptop system unless you get a rather large UPS, especially if you have a CRT monitor - desk units just aren't designed with efficiency as high a priority as laptops. . I've had good luck with APC brand UPSs.

as i mentioned preiviously, combinding a lead acide battery, a float charger, and some system of switching from battery to wall outlet is a fire and shock and explosion hazard.

well then that's not the way to do it then is it? I need a system that doesn't explode or catch fire or electricute me (ideally). there must be a way to do it, laptops have it so why can't PCs? Unfortunately i am an ideas kind of person, not too good on the execution. thats why i posted this request. Thanks for the warnings but anything i build without a guide is likely to do one or all three of those things

Do you mean [http://www.allelectronics.com/cgi-bin/item/PS-205/search/200_WATT_UNINTERRUPTABLE_POWER_SUPPLY_(AS-IS)_.html one like this?]

Oh, and if you haven't shopped at All Electronics before, it's a $7.00 flat shipping fee. It's nice to send in a $200 order and have a wimpy little $7.00 fee tacked on, instead of the typical $20-$25.

that's sort of what i need but i suspect that it is ust an LQ ups fitted into a psu and also way to low on the wattage for a modern PC. what i need is essentially a bunch of laptop batteries wired up in such a way that they are always connected to the power and the computer at the same time so when power goes there is no 'switching' involved

also 3.3 volts

not that i am aware of. i have found homemade ups plans on the internet. unfortunatly, they all seem to also be fire hazards. go to future shop (g-d i hate them) and buy a decent wattage ups like this one or this one

all a ups is is a: lead acid battery a cheap, super simple charger for the battery to stay floating a car inverter to power ac

also there's other voltages like negative and such.

any chance of someone with the technical know how to do this putting a quick guide together?