Component suggestions - Float sensor

Discussion in 'The Projects Forum' started by icydash, Jul 19, 2017.

  1. icydash

    Thread Starter AAC Fanatic!

    Jan 14, 2009
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    Hi all,

    I'm trying to build a simple circuit where a float sensor turns on or off the circuit, like the following: schematic.jpg
    Ideally, I'd like the circuit to be off until the float sensor is lifted, and then have the circuit become powered. I bought this on Amazon: https://www.amazon.com/gp/product/B00909404Y/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1 ... but it doesn't seem to be working. I'm not sure if it's only for AC or the 9v battery just isn't enough power. Does anyone have any suggestions for a float sensor that might work?

    Thanks!
     
  2. MrChips

    Moderator

    Oct 2, 2009
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    A float sensor should just be a mechanical switch.
    Take a multimeter and set the range switch to measure resistance (ohmmeter).
    Measure the resistance by connecting the ohmmeter leads to the two leads of the switch. Manually operate the switch between the two positions, ON and OFF.
     
  3. icydash

    Thread Starter AAC Fanatic!

    Jan 14, 2009
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    I think these sensors (at least the one I bought) may work by induction. I know there's a magnet in the float piece, so I think it had something to do with that.
     
  4. MrChips

    Moderator

    Oct 2, 2009
    18,862
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    If it has a magnet then it would be using a reed switch if there are only two wires.
    A Hall Effect switch would have three wires.
     
  5. icydash

    Thread Starter AAC Fanatic!

    Jan 14, 2009
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    Ok, then maybe the switch I bought is just broken. I'll try your suggested multimeter test when I get home.
     
  6. icydash

    Thread Starter AAC Fanatic!

    Jan 14, 2009
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    Weird. I just tested it and it all seems to be working now. Don't know what the problem was, but thanks for your help!
     
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