http://www.youtube.com/watch?v=S_vU4X4Mz0IThis water leak detector switch is passive and self contained.
The switch inside the brown aluminum container does not require a battery or any power source for it to sense water.
The unique reusable mechanism opens (or closes) the contacts.
There are 2 models:
Model O- The contacts will Open when a little water is sensed.
Model C - The contacts will close when a little water is sensed.
Contact Capacity: Maximum switch current: 0.5A
Voltage: 100V
Rated Power: 10W
Splice a Model O into the yellow thermostat lead of your house A/C unit to sense condensate back up overflow and it will turn your A/C compressor OFF.
Your compressor can produce a gallon an hour and a leak can cause extensive damage.
There are many uses for this leak detector; both to turn ON and to turn OFF anything you can think of.
The switch can be reset after each use.
www.water-on-demand.us uses the Water Leak Detector Universal Switch as a 24/7 back up for the system.
A few drops of water and the entire house water pressure is turned off. No water damage.
(Thanks to Brian and Dave for all your help)