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Offline Tweakie.CNC

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Re: Limit switch issues
« Reply #70 on: December 27, 2015, 03:13:06 AM »
Hi Mike,

Looking at your .xml file I notice that you do not have limit switches enabled – only home switches are enabled.
There is also a conflict (not serious but it should be avoided if possible) where X Home and EStop share the same LPT pin number 10. You also need to assign a port# to EStop.

Just to draw your attention to the relevant section of the manual…
• If you implemented configuration two from Section 4.5, you will probably have Home switches on the X, Y, and Z axes. Enable the Home switches boxes for these axes, and define the Port/Pin to which each is connected. If you are combining limits and the Home switch as one signal, then you should enable Limit --, Limit ++, and Home for each axis and allocate the same pin to Home, Limit --, and Limit ++.


Tweakie.
« Last Edit: December 27, 2015, 03:22:34 AM by Tweakie.CNC »
PEACE
Re: Limit switch issues
« Reply #71 on: December 27, 2015, 04:02:46 AM »
Hi Mike,

Looking at your .xml file I notice that you do not have limit switches enabled – only home switches are enabled.
There is also a conflict (not serious but it should be avoided if possible) where X Home and EStop share the same LPT pin number 10. You also need to assign a port# to EStop.

Just to draw your attention to the relevant section of the manual…
• If you implemented configuration two from Section 4.5, you will probably have Home switches on the X, Y, and Z axes. Enable the Home switches boxes for these axes, and define the Port/Pin to which each is connected. If you are combining limits and the Home switch as one signal, then you should enable Limit --, Limit ++, and Home for each axis and allocate the same pin to Home, Limit --, and Limit ++.


Tweakie.


Thanks, I noticed that a little earlier this evening....(like maybe 20 minutes ago lol) and since I'm at my design computer (because my cnc computer isn't connected to the net) I haven't enabled them yet...this is after I learned that one switch could be used as a limit switch and a home switch.....

Thanks for the Estop issue....how do I go about assigning a different pin to estop and a port? Frankly, I haven't used Estop in 6 years so if it is completely disabled, I wont' sweat over it....

As I'm reading through the steps to set up the switches, this is one thing that drove me to fury with the company that made my cnc....They have installed the Y home switch at 48" NOT at 0 (my table is 24" x 48"). When I contacted the manufacturer and said why is it there? that is ridiculous and how do I go about moving it to the correct location?

His answer? You dont' want to do that...
My response: why?
His answer: you just dont'

ARRRGHHHHH so for the past 4 years (took me two years to get frustrated enough to pursue it) I've been manually homing my machine because the _____ head won't give me a clear straight answer.....

Anyhow, (this is a question for all):

Is there any "danger" of burning out anything if I disconnect all my switches and wire them in series before changing the settings in Mach3?

I tell you, the first thing tomorrow (actually later on this morning after I too get some "kip" is to physically move that @%^&%#^% limit/home switch to where it should have been all along.....

Offline bfgstew

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Re: Limit switch issues
« Reply #72 on: December 27, 2015, 04:13:05 AM »
By all means move the switch, by all means rewire them so they are in series, just remember to wire them to the correct terminal on the board and set the pins correctly, (10) for your limits and (13) for your E stop, in mach3. There is no danger of magic smoke being released if you do this, unless of course you decide to wire it to mains voltage, but that would be just silly......................................but we all do silly things........................................especially when we are tired!!!!!!!
Re: Limit switch issues
« Reply #73 on: December 27, 2015, 04:19:53 AM »
By all means move the switch, by all means rewire them so they are in series, just remember to wire them to the correct terminal on the board and set the pins correctly, (10) for your limits and (13) for your E stop, in mach3. There is no danger of magic smoke being released if you do this, unless of course you decide to wire it to mains voltage, but that would be just silly......................................but we all do silly things........................................especially when we are tired!!!!!!!

that's what I figured being as how it is only 5 volts but I've made "magic smoke" before thinking that "hey, what could go wrong"? (but that's hilarious, magic smoke, I'm going to remember that lol)

One other question: on my board: there are two terminals: 5V and a pin number....I should just wire them to pin 10 and ignore the 5v (which they are currently wired to)?

Offline Davek0974

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Re: Limit switch issues
« Reply #74 on: December 27, 2015, 04:22:26 AM »
WOW!, what a thread :)

OP - you say you have CNC experience but do you have CNC machine building experience?? There is a world of difference here and from reading this thread it seems you do indeed know your CNC but not how to build one, just my presumption from the difficulties you are having with how the switches work. In a pre-built machine all this config work is done for you and the $$$$ go up, in DIY you do it yourself and the $$$$ stay down but you have to learn the intricacies of the system in use, think yourself lucky that the machine does use Mach3 and not one of the exotic flavours out there - Mach3 is probably the most flexible and easy to configure system going.

2 years ago I knew 100% of nothing about CNC, Mach3, G-Code or building a plasma cutter, 2 years later I have built two CNC tables and successfully made money out of both (for my own use). Yes I did struggle a lot at the start but the guys on here got me through.

Picking up the wiring from a machine you did not build is going to be tough, but it sounds like you are on the way now, my table only has limit switches, one at each end of travel for all axes, they are wired in series apart from one odd one as I have dual slaved motors on the gantry (Y axis) so i have it set to auto-square the gantry each time it homes.

To stop you overriding the limits and bashing the stops, I think you need two switches - a limit and a home, here the limits would be wired as e-stops only.

Are there no LEDS on your breakout board? these can be invaluable for sorting out wiring - if the switches are wired series only one LED would change for all of the switches, if parallel then a separate LED would change for each switch.

I cant see why the home would be at the top, common practice is bottom-left corner I believe and it does seem odd they said don't go there when you asked about moving it????

I am certain you will get this sorted

Offline bfgstew

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Re: Limit switch issues
« Reply #75 on: December 27, 2015, 04:41:55 AM »
Google C10 PARALLEL PORT INTERFACE CARD and the first result is the PDF for your board, your answer is there................................It does say connect to +5v and corresponding pin. But again read the information, it will help you understand how it all works.

Re: Limit switch issues
« Reply #76 on: December 27, 2015, 04:48:52 AM »
Google C10 PARALLEL PORT INTERFACE CARD and the first result is the PDF for your board, your answer is there................................It does say connect to +5v and corresponding pin. But again read the information, it will help you understand how it all works.



yeah, see, I would never consider a "pin" to be ground...to me, "ground" is the frame of the machine or a grounding terminal on the board....so if I understand this correctly, I would be connecting the limit switches to pin 10 and 5V terminals?

Offline bfgstew

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Re: Limit switch issues
« Reply #77 on: December 27, 2015, 04:55:01 AM »
That's what it shows on the PDF. Have you a multimeter at hand, so you can check voltages and switches as you work through each switch. What you are looking for (and I am sure someone more experienced than me will correct me) is 5v between +5v and pin 10, when a limit switch is pressed this should drop to 0v, then return to 5v when the switch is released i,e, a low signal, which is what Mach3 is looking for if configured correctly.
Re: Limit switch issues
« Reply #78 on: December 27, 2015, 04:57:22 AM »
WOW!, what a thread :)

OP - you say you have CNC experience but do you have CNC machine building experience?? There is a world of difference here and from reading this thread it seems you do indeed know your CNC but not how to build one, just my presumption from the difficulties you are having with how the switches work. In a pre-built machine all this config work is done for you and the $$$$ go up, in DIY you do it yourself and the $$$$ stay down but you have to learn the intricacies of the system in use, think yourself lucky that the machine does use Mach3 and not one of the exotic flavours out there - Mach3 is probably the most flexible and easy to configure system going.

2 years ago I knew 100% of nothing about CNC, Mach3, G-Code or building a plasma cutter, 2 years later I have built two CNC tables and successfully made money out of both (for my own use). Yes I did struggle a lot at the start but the guys on here got me through.



You nailed it, I am a user, not a builder....(I believe I said that early on but anyways)....when I started out 15 years ago, I drew products in autocad, loaded them into an app that converted the drawings to gcode, loaded them into the CNC zeroed it, and ran the program....didn't have to worry about the estop, limit switches configuration nothing...

Then when I decided to get a cnc of my own, (cabinet maker) I looked into building and seeing as how it was WAY over my head, I looked at buying a complete system. I looked into $10,000 state of the art systems, outside my price. I saw systems for $1000, err no an idiot pays too much but a fool pays too little. Looked around for machines in the size I needed, found one, talked to the guy, watched videos and photos, and bought a turn key system...OOPSY no it wasn't .....nothing worked the way the 4 or 5 other machines I have used...

Spent 2 hours on the phone, it kind of worked, at least enough so that I could use it....and from then on, I worked around the issues..

The reason I am addressing this NOW is because I'm going to be replacing the BOGUS plastic structural parts with aluminum and replace all the BOGUS design flaws in the machine....Where I got screwed was in the photos and videos, the black parts looked like anodized aluminum....oopsy, no, they are NYLON and I can see the fricken gantry flexing when I run programs.....hell, 2 years ago I replaced, I ********* you not, the PLASTIC gear racks and pinions with STEEL....yes, that's right, PLASTIC gears....(don't laugh) but my 2 x 4 machine was slowly becoming a 2" x 4" machine because I kept breaking teeth.....

I thought I should get the software and electronics sorted before going ahead with the mechanical improvements....I'm doing this now because this is normally a very slow time for me and it took a beating before Christmas, I made about 6 months worth of business in 7 weeks.....
« Last Edit: December 27, 2015, 05:01:15 AM by MuskokaMike »
Re: Limit switch issues
« Reply #79 on: December 27, 2015, 04:58:39 AM »
That's what it shows on the PDF. Have you a multimeter at hand, so you can check voltages and switches as you work through each switch. What you are looking for (and I am sure someone more experienced than me will correct me) is 5v between +5v and pin 10, when a limit switch is pressed this should drop to 0v, then return to 5v when the switch is released i,e, a low signal, which is what Mach3 is looking for if configured correctly.

Yes and Yes...that is what should happen if pin 10 is ground....you can also test this via a ohm meter...the resistance should be low when the switch is closed, and 100% or more when open.....btw, I should have thought of testing it myself.....DOH......the mind is a terrible thing to waste.....
« Last Edit: December 27, 2015, 05:02:07 AM by MuskokaMike »