water level sensing

Discussion in 'The Projects Forum' started by ashish4172, Oct 22, 2007.

  1. ashish4172

    Thread Starter New Member

    Dec 8, 2006

    i 'd like to develop a project that would monitor a water level in the overhead tank at home and beep if it reaches the mark set by me.

    i only want a simple ckt as i don't want to switch off pump automatically when the level reaches the set mark in tank.If i get the beep i will switch off the button.

    pl do reply with the relevant details

    ashish sharma
  2. GS3

    AAC Fanatic!

    Sep 21, 2007
  3. hgmjr

    Retired Moderator

    Jan 28, 2005
    Simple and elegant. Good suggestion.

  4. SgtWookie


    Jul 17, 2007
    The float switch will work well for quite a while; and it is quite simple.

    Better wire it up so that it is "normally closed"; that is, normally conducting electricity.

    That way, if there is a failure in making the connection, you'll be alerted.

    Another approach you might consider is a metal disk suspended above the fluid by a wire which is part of the R/C of an oscillator circuit, made with a CMOS 4093 Schmitt NAND gate, a resistor, one additional capacitor, and a piezo speaker. Select the RC values so that normally, the circuit is free-running at around 28kHz. When the water gets near the disk, it will change the frequency of the oscillator lower, into the audible range. The higher the water gets, the lower the frequency, until the disk is immersed.

    As a side benefit, when it's running with no water nearby to change the capacitance value, insects will be driven away by the high frequency noise ;)
  5. amaynew


    Jul 9, 2007
    wow SgtWookie ur suggestion is great
  6. panutronics

    New Member

    Oct 21, 2007
    use float switch which give input to non inverting terminal of opam set gain of opam to 2-3 times connect a buzzer to out put . all u required 5 v supply and 741 opam two 1k res, one res
  7. ashish4172

    Thread Starter New Member

    Dec 8, 2006
    thanks for the reply but no body has given the ckt details.pl give me the ckt
    and relevant details as i m new to this.where do i get float switch?

    pl give details

  8. mozikluv

    AAC Fanatic!

    Jan 22, 2004
  9. abhi999

    New Member

    Feb 5, 2009
    This post is quite old, though I am still writing it here if you still need it you can see this. I myself used the circuit digram and built one for me. This is the LINK http://www.electronicsforu.com/efylinux/circuit/cir105.htm of the circuit.

    I built this circuit after seeing it in that site. It worked fine though I had some problem with one part of the project which I have posted here. You should see the post here http://forum.allaboutcircuits.com/showthread.php?t=18943
    before working on the project.