On Friday 15 February 2013 19:57:59 Binand Sethumadhavan wrote:

I am thinking of something like a mobile charger that would plug in a regular 3-pin plug at one end and a computer at the other, and some software/sensor combo that would read the (DC) voltage at the computer

end.

If there is no voltage, there is no power in the mains and ergo - we are

in

the middle of a power outage, so take action. Know of something along

these

lines?

My mails to the list are getting rejected, so the direct post.

You will need either a serial or parallel port.

if you have a parallel port connect the output of the psu (PSU ouput must be 5v ) thru a 1 K resistor to pin 2 of the 25 pin dshell connector.

Use this program to read the printerport http://www.epanorama.net/circuits/portcontrol.tar

The link below provides nice info http://www.epanorama.net/circuits/parallel_output.html

You can also use the serial port with the psu wired to one odf the following inputs dcd, RI, CTS or DSR. RTS and DTR can be used as o/p via a opto isolated relay to fire your dg or alarm etc.

(idea is to detect power failures, while powered by a "dumb" UPS unit -

one

that cannot communicate with the a computer. Any other solutions/suggestions?).

you might wire the ups batteries thru a LM393 comparator and feed the op/ to pin 3. then you will be able to shut the pc when the ups is about to shut.

Or if you are up to it use a small microcontroller (pic or avr arduino) with an ADC and connected to USB.

BTW we do a server room monitoring system that monitors rack temprature and ups + mains 3 phase and send smses on failure of any of the above.

Kindly forward to the list.

Binand