Limit Switch Wiring?

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cvoinescu
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Re: Limit Switch Wiring?

Post by cvoinescu » Thu Aug 27, 2015 2:25 pm

My top guesses:
  1. you mis-configured GRBL to use the X axis input for homing both X and Y;
  2. you wired the X switch into the Y input and vice-versa.
I would go back to stock GRBL to see what happens.
Proud owner of ShapeOko #709, eShapeOko #0, and of store.amberspyglass.co.uk

chonkat
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Re: Limit Switch Wiring?

Post by chonkat » Fri Aug 28, 2015 3:18 am

Thanks. I checked the wiring and it looks pretty clean- x on 9, y on 10, z on 11 (with PWM disabled).
I could not find anything relevant to setting one axis's switch to respond for another axis either.
FACK :-)

chonkat
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Re: Limit Switch Wiring?

Post by chonkat » Fri Aug 28, 2015 8:12 pm

Switched to GRBL 0.8c y nada.
Reupdated to 0.9j, read tips again, carefully, decided to check "just in case" and saw that I had x and y inverted.
Switched wiring. BINGO!
Now I can clean up this mess and finish the wiring! Thank you.

cvoinescu
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Re: Limit Switch Wiring?

Post by cvoinescu » Fri Aug 28, 2015 9:12 pm

Told ya.

Glad you found the problem. :)
Proud owner of ShapeOko #709, eShapeOko #0, and of store.amberspyglass.co.uk

Auarhau
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Re: Limit Switch Wiring?

Post by Auarhau » Tue Sep 15, 2015 6:55 pm

So I found this from the WIKI with the title "highly-regarded wiring diagram". But after browsing through this posts, I am confused again. Which of all the diagrams here is the correct way to wire limit and homing switches? I wish there was a page on the wiki that said "This is how to wire limit switches". Right now It's a massive amount of links to this and other posts with discussions back and forth, and I have no way of telling what is the correct one (They all look Chinese to me :D )
ShapeOko 2. Nema 17 74 oz·in. GAUPS shield on Arduino Uno. DRV8825 Drivers x4 . Kress 1050 FME-1. Z Acme Screw. Threaded inserts table.

cvoinescu
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Re: Limit Switch Wiring?

Post by cvoinescu » Wed Sep 16, 2015 12:55 pm

That "highly regarded wiring diagram" is pretty basic. NC would be preferable to that, and changeover (using both the NC and NO contacts) is even better.

I can show you how I wired mine. I intentionally used unshielded cable for the limit switches, motors and the spindle (brushed DC), and bundled them together to see what happened. I've had no false triggering yet; your mileage may vary. I have a very simple circuit, with a 74HC14 hex Schmitt trigger IC (probably the same circuit used on the Carbide Motion 2.1 board, although we have no schematic for that yet). Both the NC and the NO side of each switch are wired, using three wires per switch. Because I intend to use the machine with control boards that have separate min and max limit switch inputs, each switch is wired separately, and they're connected together in series/parallel near the filtering circuit. This means that the signal for each axis goes back and forth along the bundle of unshielded cables several times, which still doesn't cause any problems (although I would recommend against it, if you didn't need it).

Needless to say, I'm very happy with the filtering circuit, and with the decision to use changeover wiring for the switches. I need to test how the limit switches behave with just the changeover wiring, without the filtering circuit, but I don't really have the time for it.
Proud owner of ShapeOko #709, eShapeOko #0, and of store.amberspyglass.co.uk

jarretl
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Re: Limit Switch Wiring?

Post by jarretl » Wed Sep 16, 2015 5:00 pm

Also if you're using GRBL v0.9h or newer, the Z limit pin is D12 by default, not D11 as indicated in that "highly regarded wiring diagram"...
Shapeoko 2 #4043; DW660

Auarhau
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Re: Limit Switch Wiring?

Post by Auarhau » Wed Sep 16, 2015 6:04 pm

Sure Catalin, I'd like to see how. But it sounds even more complicated :p I am actually unsure of even how to do the practical wiring to my arduino/gaups boards. I mean, how to acctually connect everything to pins that are "hidden" by a stepper shield. I guess I access the pins from the header thingy on top of GAUPS? But do I "stuff em in the hole", solder them in, or use a ferrule of sorts or what? It would be good if there was like a tiny break out board that connected and filtered everyting, so that dummies like myself could screw the wires in terminals and be done with it. But I really HAVE to tackle this now :? so first thing first, I need to know which diagram to follow. Can you tell I'm confused? :mrgreen:
ShapeOko 2. Nema 17 74 oz·in. GAUPS shield on Arduino Uno. DRV8825 Drivers x4 . Kress 1050 FME-1. Z Acme Screw. Threaded inserts table.

cvoinescu
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Re: Limit Switch Wiring?

Post by cvoinescu » Wed Sep 16, 2015 6:45 pm

I'll post the schematic later, because I have to draw it. In the meantime, to answer your question: the pins are exposed at the top of the GAUPS. You can use male DuPont jumper cables to plug into those. Or, you can buy a "screw shield", which exposes all pins as screw terminals (this is one example).

You may get away without the Schmitt triggers. I think the changeover wiring, while a little more complicated (three wires instead of two), makes the most sense.
Proud owner of ShapeOko #709, eShapeOko #0, and of store.amberspyglass.co.uk

Auarhau
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Re: Limit Switch Wiring?

Post by Auarhau » Tue Sep 22, 2015 11:57 am

Bumping this a bit. I really need to get this sorted. If Catalin does not have the time to post his, could someone else point me to which of the diagrams in this thread is the correct one? I did some tries from what I understood from the wiki last night, but nothing happened :p . Also, there are ground pins on both sides of the Arduino, does it matter which one I use?
ShapeOko 2. Nema 17 74 oz·in. GAUPS shield on Arduino Uno. DRV8825 Drivers x4 . Kress 1050 FME-1. Z Acme Screw. Threaded inserts table.

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