I am designing a system to monitor a home while the residents are absent for an extended period. A feature I wish to include is a means to determine if water is somehow leaking into the premises from rain storms. Obviously, I can't put leak sensors everywhere, but if I could find some sort of twin-lead cable whose insulation could soak through (like old fashioned magnet wire wrapped in cotton) I'd be able to monitor resistance, and perhaps sense water on a floor. The nice thing is that a single cable could be threaded back and forth to cover a lot of area.
So my question is, does anybody have a candidate for such a use? Thanks in advance for any ideas.
Use a 10k pullup resistor on the open collector output. HIGH = NO LEAK,LOW=LEAK
The chip datasheet says the supply voltage is 16vdc but it might work at 5v. If you used 16v you would need a 5V zener diode across the output pin to ground, with the cathode on the output pin, anode to ground. It surely would work on a 12V lantern battery , the square batteries that are 3'x 3" square and about 5" high. I used the LM1830 chip once and it was simple to use. Just get to pieces of bare copper wire and stick them though a small piece of sponge (or hot glue them together so they don't touch) about 1 cm apart and lay that flat on the floor. If you want to get creative you can do two "S" pieces with one upside down so it covers a 3" x3" square with the bare copper touching the floor. You can test it with a squirt-gun or just flick some water on it. or you could try this [http://www.ebay.com/itm/New-Water-Sensor-for-Arduino-Moisture Water-droplets-Water-Depth-detection-/330992002679?_trksid=p2054897.l4275 ](http://www.ebay.com/itm/New-Water-Sensor-for-Arduino-Moisture-Water-droplets-Water-Depth detection-/330992002679?_trksid=p2054897.l4275)
Thanks for the tip. After looking at the product, it is probably quite easy to create, if you etch your own boards, and I do. So I'll get busy and make it my next little science project.