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  1. #1
    Join Date
    Oct 2007
    Posts
    152

    LIMIT SWITCHES

    Hi to all
    I am just about done building my router table, for the electrical parts it goes like this: four Kelling 905 Oz/in ( Unipolar wired 640Oz/In ) with belt reduction 3:1 four Gecko 203V and a Pmdx 122 BOB, two limit switch on each axis running with Mach3. Everything is working properly except for the following.

    The problem that I'm having is that when I make a Ref All Home the limits seems to be slow to react and the axis passes the limits and when it redraws to set the zero it's always inconsistent sometime it won’t even return enough to return over the limit and when I try to move that axis it triggers the limit switch.
    My debounce in Mach is set at zero just in case you might ask, the wiring that I'm using are 20 gauge shielded
    Any help would be appreciate

    Thank you
    PS when I manualy operate the switches everything is ok

  2. #2
    Join Date
    Feb 2007
    Posts
    4553

    Post

    Bobinette,

    Please tell us more about what type and brand of switch you are using?

    Posting a picture may help also.

    If the acceleration is set to low the axis will over travel the limit switch.

    Try raising your acceleration rate.

    Jeff...
    Attached Thumbnails Attached Thumbnails Acceleration.JPG  
    Patience and perseverance have a magical effect before which difficulties disappear and obstacles vanish.

  3. #3
    Join Date
    Oct 2007
    Posts
    152
    Hi
    As usual, you where right about the acceleration, it works for the Y and Z axis but the X still have overruns.
    What will be a reasonable acceleration to set my table?
    Thank you
    These are the new settings before it was at 1.25 for the X and Y and Z at 1
    Attached Thumbnails Attached Thumbnails X axe.jpg   Y axe.jpg   Z axe.jpg  

  4. #4
    Join Date
    Feb 2007
    Posts
    4553

    Post

    Bobinette,

    When you snap "push and rapidly release" the page up or page down keys the axis should stop instantly. Keep bumping up the acceleration until the axis stops on a dime when you snap the keys.

    Try a starting point for the acceleration at about 15% of the velocity then bump it up from there.

    Use the same procedure for the Left & Right - Up & Down Arrow Keys.

    Jeff...
    Patience and perseverance have a magical effect before which difficulties disappear and obstacles vanish.

  5. #5
    Join Date
    Oct 2007
    Posts
    152
    Hi, for the 15% it was on the button, I was thinking that lower was the way to go, I had it low to avoid stress on the motors on the startup, this shows me that I have a lot to learn.
    Thank you

  6. #6
    Join Date
    Oct 2007
    Posts
    152
    Hi, well when I first posted, I have mention that everything was alright except for the switches, but this wasn't quiet threw because I haven't try a slow jogging.

    On the Y axis where I have two motors connected it is noisy and runs rough.
    I have tried to fine tune the Geako with little success.
    The others drives are very smooth.
    Any idea?
    Thank you

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