AVR-Chat

Back when I was at Uni a few years ago, one of the students had a project to electronically measure the water level in a plastic tank. Best way I have seen this done is run two parallel metal plates along the depth of the tank and then look at the change in capacitance between the two plates based on the amount of water between the plates. As the water level dropped, the capacitance would decrease because the relative permeability of water is higher than air . . . (Hope I remembered all this correctly) Set this up as a oscillator with frequency based on capacitance and you have a varying output frequency based on the water level.

Hein B
Auckland, New Zealand.

--- In AVR-Chat@yahoogroups.com, "Brian" <blue_eagle74@...> wrote:
>
> I think the best non-movement sensor would be a presure sensor at the bottom of the tank. No moving parts and it can be sealed. So it could measure many liquids.
> 
> Brian
> 
> --- In AVR-Chat@yahoogroups.com, Muhammad Amiruddin <amiruddin.muhammad@> wrote:
> >
> > Dear all,
> >  
> > please help me,
> >  
> > i want make project for measuring the level of water on the tank that approximately 15 m high. what senssor that i should use ?
> >  
> > Is there any ultrasonic senssor wich can measure range until 15 m ?
> >  
> > rgds,
> >  
> > 4mir
> >  
> > 
> > 
> >       
> > 
> > [Non-text portions of this message have been removed]
> >
>