Electronics Tutorial Anyone?

Discussion in 'Tutorials' started by redpiperbob, Jul 31, 2018.

  1. redpiperbob

    redpiperbob Full Member

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    Before we start on the point motors I thought you might like to see a mock up of the layout based on the drawings in the previous post.
    One thing I forgot to mention is there are many ways to wire the same scenario I have just used one.

    Be seeing you
    Bob
     
    SMR CHRIS and jakesdad13 like this.
  2. redpiperbob

    redpiperbob Full Member

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    And here is a view inside the switch box

    Be seeing you
    Bob
     
  3. redpiperbob

    redpiperbob Full Member

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    Now for the point motors

    The ones here are the Gaugemaster GMC-PM10 (seep).

    Here are a couple of pictures of the PM10’s
    These solenoids are reliable and easy to fit and very easy to electrically connect.
    For those that don’t know how a solenoid works here is a brief description
    If we apply the correct voltage between A and B the iron plunger inside the coil of wire

    will be attracted to that coil. Now if we have two coils on the one plunger as in this picture.
    If we apply a voltage to A and C the plunger will move to the left.

    If we apply a voltage to B and C the plunger will move to the right.

    This is how the point motors work.



    In the above picture the two black arrows are the coils and the blue arrow is the plunger.



    Now to get the solenoid plunger to move positively we need to give the coils a quick surge of current. We cannot leave the current on as this would burnout the coil wiring. To do this we need a different kind if switch then the single pole on/off type we used to connect to the track.

    There are many ways of giving this short sharp blast of current, probe and buttons, passing contact switches or press to make button switches. The one we will use here is the passing contact switch. There are many different switches we will use a center biased switch this is a switch that is sprung loaded to the middle and can be pressed either way to momentarily connect to either of two contacts

    The other thing we need to give that last of current is a Capacitor discharge unit (CDU), this unit is feed from a 12 to 16 volt power supply and when activated sends out a short pulse of high current.

    The following is a wiring diagram of one point motor connected to a CDU.

    Here are the connections on the point motor


    Here are the connections to the CDU
    The two blue arrows are the PSU connections
    The red arrow is the connection to Z on the passing switch
    The black arrow is the connection to the C connection of the point motor.
    And here is the diagram to all three points.
     
  4. redpiperbob

    redpiperbob Full Member

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