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water meter and ds2423 problem

Posted: Thu Aug 18, 2011 9:41 pm
by promy
in my new house i installed 3 watermeters from aquatel, wich have a pulse connector.
Normally the reed contact is open (no connection), but when the magnet passes the reedcontact closes.(connection) (and could stay closed when the meter stops on the magnet).

I tried connecting this sensor between the ds2423 A connector and the +5V. But i get strange readouts...
So i went looking, and it seems when I connect the A connector with 5V i get an incement of the counter(so thats ok), but more than one (seems to be related to the time it's connected.)

Does anyone have a solution for this problem ( or a working schema?)
Thanks!

Re: water meter and ds2423 problem

Posted: Thu Aug 18, 2011 9:59 pm
by Menno
It seems like you need some sort of circuit to make a neat pulse from the watermeter output. Even when the meter stops on the switch you want a short pulse. This can be achieved by using a Monostable Multivibrator like 74LS221 IC. I have used this one for my gas and watermeter. Unfortunatly I do not have a schematic, because it was made on a sunday afternoon on a breadboard. Read the datasheet carefully and with some experience on electronics you must be able to make a circuit.

Re: water meter and ds2423 problem

Posted: Sat Aug 20, 2011 3:30 pm
by promy
this sounds like a solution! however, my experience on electronics isn't so great.... so i am not so sure what circuitry i need around it...
can anyone help with a scematic?