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Mk111 Variable interval timer!

  1. Jan 6, 2007 #1
    I hae built a MK111 variable interval timer http://www.maplin.co.uk/Module.aspx?ModuleNo=25224&criteria=TIMER KITS&doy=6m1"

    and intend to use it for a free-flight glider which is a university project!

    I wish for the timer to power an electric motor for 2sec and then pause for a desired time peroid such as 5sec before having another 2 sec of power to the motor! Which is exactley what the circuit is for!

    My question is regarding the conections on J2 which are NO, NC and COM these are from the relay.

    I can curently get the motor to run through the circuit but cannont get it to interupt the motor as required!

    How should the motor be wired to the conections on J2? ie the motor and the battery??

    The instructions/ circuit diagram can be found here:

    http://www.vellemanusa.com/downloads/0/manual_mk111.pdf" [Broken]

    any help would be much aprciated!
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Jan 6, 2007 #2
    I'm not for sure exactly how your relay is connected on the PCB, but I'm assuming your motor is rated for 12V (check this!). You would probably want to connect +12V (from the battery) to the relay's COM (common) and then hook your motor up to the NO (Normally Open) terminal. Your other motor terminal would then connect to your -12V (from the battery). This way the motor would turn on when the relay was energized. You could reverse this operation by hooking your motor between the NC (Normally Closed) and -12V.
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