if all limit switches are wired in series, how does it know which is which?

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rk9268vc
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if all limit switches are wired in series, how does it know which is which?

Post by rk9268vc »

The hookup schematic "S14954-ACORN_rev4_LIMITALL_HOMEALL" shows all the limit switches wired in series.
How does that work?
Does it only home one axis at a time?
How does it know which axis is tripping the switch?
If one is tripping the switch, how will it tell if the other axis reach their switch?

Confused.exe
tblough
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Re: if all limit switches are wired in series, how does it know which is which?

Post by tblough »

Use the search box in the upper right to search on "homeall". Many posts explaining how it works.
Cheers,

Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
lavrgs
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Re: if all limit switches are wired in series, how does it know which is which?

Post by lavrgs »

In the wizard you can set the order of axes to home e.g.Z (3) first, then Y (2) then X(1) would be typical for a mill. You also set direction but based on your question if you place a limit switch on the X axis, because they're in series it shouldn't matter where in the series it's wired - when tripped it opens and breaks the path. Just check to make sure all the switches open and close.

HTH
cncsnw
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Re: if all limit switches are wired in series, how does it know which is which?

Post by cncsnw »

A key point to understand is that home is just clear of the switch, not on the switch.

Since each axis moves clear of the switch after tripping it, and only one axis homes at a time, the code can assume that the axis that is in motion is the one that tripped its switch.

That is why you cannot start homing if a switch is already tripped. You have to jog clear first.
rk9268vc
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Re: if all limit switches are wired in series, how does it know which is which?

Post by rk9268vc »

cncsnw wrote: Fri Oct 08, 2021 11:21 pm A key point to understand is that home is just clear of the switch, not on the switch.
Oh that makes a lot of sense. I didnt realize they backed off the switch automatically.

Thanks!
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