An even easier way is to use the air pump in the fish tank.. Place a tube at the bottom of the fish tank with no airstone on it.
Set the air flow to slowly bubble air out the bottom of the tube at the "full" water level. Place a T in the air line, after the regulator valve and connect a solid state pressure sensor like one of these: <http://www.omegadyne.com/ppt/prod.html?ref=PX138> (I've seen others at a much lower price!) As the water level drops, the pressure in the hose will drop to equal the depth of the water at about 2.31 lbs per foot of depth. Should the air pump fail, it will look like the water level is dropping.. and in either case you'd want to investigate the readings. Monitoring the input air pressure with a separate sensor would give you a fail safe method of knowing which was which. It will work well in all sorts of climates, because the only thing that needs to be exposed is the air hose.. every thing else can be in a protected environment. Steve ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Owfs-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/owfs-developers
