UPS (uninteruptable power supply) for computer - Electronic Circuits Projects Diagrams Free

Maury · 19th August 2003, 11:31 PM

Rather than purchase an expensive store-bought UPS, why not just use a 12 volt auto battery (perhaps with mains charger) along wiith appropriate voltage regulators (with nec. circuitry) , say, 12vdc , 5v and 3.3 v for emergency computer power? Dumb question?

ops:

nettron1000 · 19th August 2003, 11:58 PM

No not a dumb question at all, thats what a UPS is mainly composed of. Its just that you left out the DC to AC convertor part.

The biggest problem with building your own UPS supply is in getting a good sinewave output. Even some of the store bought units dont produce a perfect sinewave output UPS, eventhough they will boast that they do.

Maury · 21st August 2003, 08:47 PM

Nettron 1000 . Thanks for the answer to my question! Also, thanks to this net and the unselfish responders. I will keep on board>

nettron1000 · 21st August 2003, 11:26 PM

NP, hey welcome to the board.

There was a thread running a while back about DC to AC invertors that you may be interested in:

http://www.electro-tech-online.com/viewtopic.php?t=1287

nettron1000 · 22nd August 2003, 12:03 AM

...and heres another more informative one:

http://www.electro-tech-online.com/viewtopic.php?t=2695

Maury · 26th August 2003, 09:38 AM

Don't computers use only dc, 12v, 3.3v etc? Why do we need to invert the battery voltage, say, 12vdc to AC and then use a power supply to convert down to some dc level? I think I was behind the door when they passed computer smarts. :?

Sebi · 26th August 2003, 12:06 PM

Because for consumers need only two connections...
and computers haven't 10...20A sockets for supply input. I've seen old ATPSU-s with in-built inverter and 12V 7Ah accu.
Of course possible to build PSU for PC with multiple outputs from 12V, but this is expensive.

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19th August 2003, 11:31 PM	(permalink)
Maury	UPS (uninteruptable power supply) for computer Rather than purchase an expensive store-bought UPS, why not just use a 12 volt auto battery (perhaps with mains charger) along wiith appropriate voltage regulators (with nec. circuitry) , say, 12vdc , 5v and 3.3 v for emergency computer power? Dumb question? ops:

19th August 2003, 11:58 PM	(permalink)
nettron1000	No not a dumb question at all, thats what a UPS is mainly composed of. Its just that you left out the DC to AC convertor part. The biggest problem with building your own UPS supply is in getting a good sinewave output. Even some of the store bought units dont produce a perfect sinewave output UPS, eventhough they will boast that they do. __________________ Two roads diverged into a woods...i took the one less travelled by. R. Frost.

21st August 2003, 08:47 PM	(permalink)
Maury	UPS (uninteruptable power supply) Nettron 1000 . Thanks for the answer to my question! Also, thanks to this net and the unselfish responders. I will keep on board>

21st August 2003, 11:26 PM	(permalink)
nettron1000	NP, hey welcome to the board. There was a thread running a while back about DC to AC invertors that you may be interested in: http://www.electro-tech-online.com/viewtopic.php?t=1287 __________________ Two roads diverged into a woods...i took the one less travelled by. R. Frost.

22nd August 2003, 12:03 AM	(permalink)
nettron1000	...and heres another more informative one: http://www.electro-tech-online.com/viewtopic.php?t=2695 __________________ Two roads diverged into a woods...i took the one less travelled by. R. Frost.

26th August 2003, 09:38 AM	(permalink)
Maury	UPS Don't computers use only dc, 12v, 3.3v etc? Why do we need to invert the battery voltage, say, 12vdc to AC and then use a power supply to convert down to some dc level? I think I was behind the door when they passed computer smarts. :?

26th August 2003, 12:06 PM	(permalink)
Sebi	Because for consumers need only two connections... and computers haven't 10...20A sockets for supply input. I've seen old ATPSU-s with in-built inverter and 12V 7Ah accu. Of course possible to build PSU for PC with multiple outputs from 12V, but this is expensive.