Relay Logic Clock Signal

Discussion in 'General Electronics Chat' started by scoobydoo, Nov 25, 2013.

  1. scoobydoo

    Thread Starter New Member

    Nov 25, 2013
    I'm trying to solve a problem for school by converting a state diagram to a logic circuit then converting that to ladder logic. I've already solved the problem by brute force, but I want to develop a systematic approach. My labs will be only be getting more complex. Of course as I go beyond 6 inputs then I will automate the process using matlab.

    The process is fairly clear if not that easy to do. I've been following this guide:

    I end up with a circuit using D flip-flops. However, its never explained where the clock signal comes from. How do I implement a clock signal using relay logic?

    I think the answer is on this page, but I don;t get it:

    Thanks, Scooby
  2. strantor

    AAC Fanatic!

    Oct 3, 2010
    You use a timer relay. Timer relays come in many varieties; some delay closing after a signal is applied, some delay open after signal is removed, some generate a pulse when signal is applied, etc. Some contain electronic circuits to handle the timing, some use a pneumatic cylinder with orifice valve to control timing.
  3. scoobydoo

    Thread Starter New Member

    Nov 25, 2013

    But the timer implements an edge detector, its not the clock itself. I'm assuming that if you hooked up a normally open push button in place of the C contact then that could be your clock signal. I guess I've been thinking of the clock as synchronous whereas the real world processes are asynchronous.

    I'm going to work on that now. I'll post updates as I go along.