On Sun, Jul 07, 2013 at 04:21:17PM +0200, Jan Kandziora wrote: > Another possible method working with both water and non-polar liquids is > checking the dielectrical permittivity, same method as a capacitive > touchscreen uses. There are really cheap ICs for that purpose out there, > but they all have to be calibrated carefully and in your installation, I > doubt the calibration data needed is stable enough in the long run.
I expect it is more reliable than a thermal approach. I would get a teensyduino 3.0 with its built in capacitive sensing pins and program that to detect water against a suitable capacitance probe. The teensy can turn on a pin, or report its measurements over usb. the teensy will cost about $20, the sensor can be made from a pcb sprayed with waterproof paint and the software is provided in the examples in the arduino ide. njh ------------------------------------------------------------------------------ This SF.net email is sponsored by Windows: Build for Windows Store. http://p.sf.net/sfu/windows-dev2dev _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
