On 6/26/07, Miguel Reznicek <mreznicek@pretensa.com> wrote:
> Friends:
>
> Does someone know of a PIC chip circuit that will monitor the 220 VAC mains
> and use them to run, but that can automatically switch to a battery power
> when the mains fails?  I need to make an alarm for when the power fails.
>
> Thanks in advance,
>
> Miguel Reznicek
> mreznicek@pretensa.com

I have a design here http://www.vscp.org/wiki/doku.php?id=rockhampton
Here The voltage sense is used to check the status for some lamps
(really relay outputs).

For power a 12V power source and a 12V SLAB connected to a charge is
used. A standard 110V/230V switching relay is used  that switch
between battery vs. power supply as the design  can live with power
going away as long as the system goes up again.


Cheers
/Ake

-- 
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Ake Hedman (YAP - Yet Another Programmer)
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