I found a really cool water level sensor on adafruit made by Chris Milone of Milone technologies:
http://www.milonetech.com/Home_Page.html http://www.adafruit.com/product/464 I contacted Chris about a custom length for a diesel heating-oil tank meter I'm trying to build. It's a little pricey, but is a neat idea as it doesn't require a float. On Thu, Dec 4, 2014 at 7:35 PM, Mr Yum <[email protected]> wrote: > Mathew Lippincott <[email protected]> wrote: > > > you can measure the capacitance of a wire to determine depth. here are > > some plans, this device uses the changes in a 555's R/C circuit to > measure > > the capacitance change. > > http://njhurst.com/electronics/watersensor/ > > > > here's some notes on replicating and simplifying that circuit to just > > sample the output of the 555 directly (work in progress). > > > http://publiclab.org/notes/laurenrae/11-24-2014/don-explains-the-theory-behind-the-depth-sensor-for-the-riffle > > I worked for a automotive vendor years ago that made fuel gauges, some of > which used capacitance. However, most of their units used magnetic reed > switches wired in parallel w/ resistors on a long tube-mounted circuit > board. The float had a magnet that triggered the reed switches. The > output is a step function but apparently accurate enough for most truck > gauges. The nice thing about the design is it can be adjusted to account > for irregularly shaped tanks. > > Magnetic reed switches at HobbyLinc: > http://www.hobbylinc.com/htm/bra/bra3530.htm > _______________________________________________ > dorkbotpdx-blabber mailing list > [email protected] > http://music.columbia.edu/mailman/listinfo/dorkbotpdx-blabber >
_______________________________________________ dorkbotpdx-blabber mailing list [email protected] http://music.columbia.edu/mailman/listinfo/dorkbotpdx-blabber
