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Designing a timing device.

  1. Dec 15, 2008 #1
    Hi guys,


    There are 2 relays, A and B that needs to be controlled (24V)

    And a signal generating device that composes of a push button and an adjustable mechanism for timing delay between the 2 signals. (this is what I want to design)


    I want to design a device that, when I press the push button, relay A is activated for 1 second. Meanwhile, relay B is activated after a delay (of 150~300ms adjustable) after relay A is activated. Relay B also activates for 1 second.

    Does anyone know if there are avaliable eletronic products that will aid me for this purpose?
    Such as an "adjustable delay timer" etc.

  2. jcsd
  3. Dec 16, 2008 #2
    mcmaster.com has a ton of timing relays.
  4. Dec 16, 2008 #3
    Thanks Proton, but I looked through mcmaster, the timing relays are in the range of second~hours while I need a delay in the order of milliseconds.

    Secondly I think I dont need a timing "relay". I want to control my relay with a time delay device.
  5. Dec 16, 2008 #4
    oh, yeah, milliseconds is pretty fast for what they have. i think i would start looking at designing something with 555/556 timers and some logic gates.
  6. Dec 16, 2008 #5


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    Here's a good place to start for using http://en.wikipedia.org/wiki/555_timer_IC" [Broken].
    Last edited by a moderator: May 3, 2017
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