Hello Guest it is June 16, 2019, 07:28:09 AM

Author Topic: Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!  (Read 11708 times)

0 Members and 1 Guest are viewing this topic.

Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!
« on: December 14, 2007, 02:18:51 AM »
Hello All,

Well I am trying to set up my home and Limit switches and I am getting  frustrated to say the least. I have watched the video and it does not run through it completely unless I am brain dead or something of that nature, maybe I am just at my wits end and cant see it.

The Problem.....


I have six switches all in NC and wired in series, all at the end of the three axis. I want to use the X-, Y- and the Z+ as the homing switches. Well I don't know what pins I put them to or if they are supposed to all be high or low active or what. Also when I did the automated setup it put them all at 15. I made the home switches 11 only because the video did, and now I have no clue as to whats what.

I have added a picture of what I have.


Question ...

Can someone please tell me what the pins are supposed to be?

Setup ...

X2 HF Mini Mill
Hobby CNC Pro Board
Keling Technology KL23H286-20-8B Steppers on X,Y,and Z
Mach3


Any Help would be GREATLY APPRECIATED!!!!

Thanks
Bill

Offline Hood

*
  •  25,843 25,843
  • Carnoustie, Scotland
    • View Profile
Re: Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!
« Reply #1 on: December 14, 2007, 03:03:50 AM »
If you have all of yopur limits wired in series then you will only be using 1 pin on the port, this is the pin that you enter for all limits and also all homing. So if as in your example you are using pin 15 for the limits the home switches will also be pin 15 as essentially the home switch is a limit switch. When Homing Mach treats the limit switch as a home switch, at all other times its a normal limit switch.
 If you want to change the direction of your homing have a look on the Config menu then Homing and Limits page and then you can choose whether to home negative or not.
Hood
« Last Edit: December 14, 2007, 03:07:11 AM by Hood »
Re: Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!
« Reply #2 on: December 14, 2007, 12:29:26 PM »
Hood,

Thanks for your reply!

One question though,

I tried to set it up so when it hits the home switch, it will back off of it automatically but I cant seem to get it to do that, How does that work and were do I set that up at?

Thanks Again
Bill

Offline stirling

*
  • *
  •  2,188 2,188
  • UK
    • View Profile
    • www.razordance.co.uk
Re: Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!
« Reply #3 on: December 14, 2007, 01:16:23 PM »
I tried to set it up so when it hits the home switch, it will back off of it automatically but I cant seem to get it to do that, How does that work and were do I set that up at?

Hi Bill - You don't have to set anything up. The backoff is part of the (inbuilt) homing behaviour. Not of course to be confused with hitting a limit which does not backoff. Are you saying when you command home it doesn't backoff?
Re: Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!
« Reply #4 on: December 14, 2007, 01:35:09 PM »
Stirling,
Just to clarify......... If you JOG into the switch, it should just stop instantly ?
But if you command the axis to HOME, it goes through the homing sequence of tripping the switch then backing off the preset amount in the software ?
Thanks

Offline Hood

*
  •  25,843 25,843
  • Carnoustie, Scotland
    • View Profile
Re: Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!
« Reply #5 on: December 14, 2007, 01:54:15 PM »
Yes thats correct, if you accidently Jog (or your programme) hits a limit Mach will stop instantly. You can also set up soft limits so that as you are approaching a limit switch Mach will slow and stop before you hit the switch and warn you that the soft limits have been activated. This also has an advantage as when softlimits are set and you load some code and press the Cycle Start button Mach will look and see if any of the movements in your code will cause an axis to be out of limits, if it is then you will get a message box asking if you are sure you want to continue.


Hood

Re: Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!
« Reply #6 on: December 14, 2007, 02:49:07 PM »
Stirling - Hood,

I was jogging to test the switch and I can see how that will not work. I will need to  try and hit the home all and see if that works. I do want to use the soft limits so I need to set that up also. Boy this is harder than the haas here at work!

With that all said, I cant wait to get her set up and test this out properly so I can buy the software. BTW - I really like it, it's just a little overwhelming at times.

Thanks again guys
Bill
Re: Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!
« Reply #7 on: December 14, 2007, 11:20:08 PM »
Well guy's

When I got home from work, I went into my shop and fired her up. I hit the Ref All Home bar and it hit the Z switch and DID NOT back off. I am including a picture of the two menus.

What could it be?

Thanks
Bill

Offline Hood

*
  •  25,843 25,843
  • Carnoustie, Scotland
    • View Profile
Re: Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!
« Reply #8 on: December 15, 2007, 04:43:50 AM »
Does the LED for the Home stay on (Diagnostics page) when the switch is triggered? Does that axis show as being homed ?(Green LED on Axis Zero button)

Hood

Offline stirling

*
  • *
  •  2,188 2,188
  • UK
    • View Profile
    • www.razordance.co.uk
Re: Home and Limit Switches ... I'm Going Crazyyyyyyyyy!!!!!!!!!!!!
« Reply #9 on: December 15, 2007, 04:46:21 AM »
Things that could potentially stop the homing procedure finishing properly:

1) switch bounce leading Mach to "think" it's come off the switch prematurely. see config/general config - debounce (top right of dialog)
2) your switch is prematurely closing for some other reason - coming off the cam/ramp whatever perhaps? - i.e. once a home switch is hit it must stay hit until Mach has a chance to roll off.

edit: Hood posted while I was composing - looks like we're thinking similarly :)
« Last Edit: December 15, 2007, 04:48:21 AM by stirling »