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Creating on/off capability using same normally opened P.B

  1. Oct 25, 2016 #1

    Excited to design, using relays, corresponding switches and timers, a control diagram that has a function as follows:

    When user presses the push-button, a lamp turns on and remains that way (self-latched). After a small time delay when the user re-presses the same push-button the light goes off and so on repeatedly...

    Regularly in control diagrams, there are several logic laws that user must obey in order to have an efficient system functioning. In this case, a single input CANNOT create different outputs.[1]

    I know that there are self-latching relays, and one can program a chip to make a counter and do this small function, but the intention is to exercise drawing industrial control montages.
    Before posting problems related to [1], I have used a single push button with an N.O switch and another N.O auxiliary one that both function under the same order of button switch. The circuit is as follow and is 100% functioning:


    I've labeled the push buttons as 1 referring to two N.O switched for the same P.B

    The purpose of creating this thread, is to hear comments, and opinions whether if the above circuit is achievable using a single N.O switch from the push button instead of two, without disregarding law referred as [1].

    I have such circuits but all of them failed, due to the fact that the same N.O switch even if interfaced to timers, cannot make more than one decision that is passing current or not.

    Since all were failed, no need to upload them.

    Awaiting your comments.
  2. jcsd
  3. Oct 25, 2016 #2


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    your circuit is difficult to comprehend, and is not helped by the fact that all your resistor labels are capacitors

    how about redrawing the circuit and this time use the correct symbols and labels so we can see more correctly what your circuit is trying to show

    also show connections for power supply, label them + and - and indicate the voltage used

  4. Oct 25, 2016 #3


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    The OP is using the Industrial Control, Electrician, convention for the schematic

    What we Electronic folks would consider a capacitor, are Normally Open relay contacts in their language, with the "R" designation here denoting a "Relay". You will notice that R1 contact has a slash thru it to denote Normally Closed contacts. The rectangles with a slash thru them are relay coils.

    On the extreme right, the Circle with an inscribed X is a lamp (slightly non-standard representation).

    On the left, top, the symbol labeled "1" with a sideways "T" is a Normally Open Push Button.

    (edit) p.s. A search for Ladder Logic or Industrial Control may find some standards for these symbols.
  5. Oct 25, 2016 #4


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    Im not an Industrial Control, Electrician. I'm an electronics tech ... that's not how we techs draw relay contacts it's how we draw non polarised caps :wink:

  6. Oct 25, 2016 #5

    Dear Dave,

    No matter what professional you are, if you read right the description I've wrote before uploading the image you can comprehend what I was talking about. Symbols are after all tools to ameliorate comprehension. A non polarized capacitor, generally a ceramic capacitor in electronic circuit can be drawn like N.Os are drawn in my circuit, but if so, the circuit makes no sense, bunch of resistors and capacitors in series/parallel would be flu.
  7. Oct 26, 2016 #6


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  8. Oct 26, 2016 #7


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    I have no idea what you just posted. Thread locked until you can send me a message explaining yourself.
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