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Author Topic: Yes, another home limit switch question.  (Read 3428 times)

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Offline Jackal

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Yes, another home limit switch question.
« on: May 18, 2011, 05:04:46 PM »
 
On my mill, it will use (4) limit switches.   

 Z+, Z-, X , and Y. These will be NC switches connected to pin #12.   On X  & Y,  switch is mounted in middle and trip dogs will trigger them.

After reading some of the posts on here,  others tell of using the same switches for homing????????????

How does that work?

I know Mach disregards the limits when homing. My B_O_B has only 4 inputs for I/O, wouldn't you   have to wire  each axis  to the 3 remaining inputs separately?

 I am a little lost on this. Some say they have the home switches wired in series.  Once this gets clear in my head, it will seem so simple.

Thanks for the help,

JAckal ;D

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Offline ger21

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Re: Yes, another home limit switch question.
« Reply #1 on: May 18, 2011, 05:29:42 PM »
You assign the home switches to the same pin in Mach3, no additional wiring is needed.
Gerry

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Offline Hood

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Re: Yes, another home limit switch question.
« Reply #2 on: May 18, 2011, 05:30:26 PM »
If you have all switches connected in series and use one input then when Homing you can only move one axis at a time, the order of which is determined in the RefAll button, standard is Z then Y then X then A.
So what happens is Mach starts homing, sees the switch and presumes its the axis thats moving as it cant really be any other, reverses and sets home then moves to the next etc.
Hood

Offline Jackal

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Re: Yes, another home limit switch question.
« Reply #3 on: May 18, 2011, 07:29:59 PM »
OK, Then it homes out each axis in sequence.

That is too cool. Mach is really amazing!!!!!!!!!

Thanks,
JAckal  ;)
Everything is bio-degradable if you run over it enough with a lawnmower.

Offline kf2qd

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Re: Yes, another home limit switch question.
« Reply #4 on: May 19, 2011, 10:02:10 AM »
Another way that might be easier to troubleshoot is to use 3 inputs, 1 for each axis.  You can use 2 limits for each axis, wired normally closed wired to each input. set the positive, negative and home to the same input. I have a KX 3 that is wired that way, Had a problem when I first tried homing because the X & Z were swapped in the settings. For best results you might want to make sure the limit that is used for home is a good quality switch so the home position doesn't wander...

Offline Jackal

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Re: Yes, another home limit switch question.
« Reply #5 on: May 19, 2011, 05:19:57 PM »
kf2gd,

That crossed my mind  (3 separate inputs).

I really just want one limit switch on the X & Y axis. Have it in the middle (protected), and a ramp at each end of the axis to trigger it.

The Z already has 2 switches fully enclosed.

Thanks,

JAckal
Everything is bio-degradable if you run over it enough with a lawnmower.