Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Optical sensor on/off

  1. Sep 14, 2013 #1
    Hi all I would like some ideas and pointers on how you think that I could drive my electromagnet to turn on/off with some form of optical sensor. I’m using a 12V 3.6A battery. I’m not too knowledgeable in the optical sensor arena. So if you have any ideas on how I could drive this inductive load give me your thoughts, thanks.
  2. jcsd
  3. Sep 14, 2013 #2
    What do you want the optical sensor to sense? A break in the beam would toggle power to the electromagnet?
  4. Sep 14, 2013 #3
    yes, sorry for not making that clear.
  5. Sep 14, 2013 #4
    You might want to consider a photointerrupter. And some basic digital logic to control a digital mosfet.
  6. Sep 14, 2013 #5
    I'v looked into them, I did not know of any others that may be easer.
  7. Sep 14, 2013 #6
    I have just one more question. Do you need the optical sensor as a safety device such that power to the magnet is cut off when the beam is cut or to mimic the behavior of a switch?
  8. Sep 15, 2013 #7


    User Avatar
    Gold Member

  9. Sep 15, 2013 #8
    I need it to mimic the behavior of the switch. I like the idea of a relay but relays have limited life's and don't last for as much repetitions as I need.
  10. Sep 15, 2013 #9


    User Avatar
    Gold Member

    Then find a solid state photoelectric switch. Granger has them, but they are expensive.

    Google "phototriac coupler".
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Optical sensor on/off
  1. Vibration sensor (Replies: 4)

  2. Motion sensor (Replies: 5)

  3. Sensor Failure (Replies: 1)

  4. What is this sensor? (Replies: 1)