Machsupport Forum

Mach Discussion => FAQs => Topic started by: Chieffy on August 08, 2011, 07:47:03 PM

Title: z home switch
Post by: Chieffy on August 08, 2011, 07:47:03 PM

Good day:

I am new to CNC and Mach3 and am also having issues with the switches.  I have hooked up all my switches and when i ask the machine to home itself the z switch turns system off , it does not back off the switch as do the y and x axis home switches.  I have made sure that the z switch is found as a home switch only and even played with resetting the home zero after backing it of .25".

The funny part is it worked once. When I first set up all my switches and axis were all over the place I pressed  home and all homed nicely. Z than y and finally x. The problem is it has never worked since.

As z is the first axis that homes it stays on off and I have to manually back it off and hit reset. Than it just homes z again etc.

Any help would be greatly appreciated.

Chieffy

Title: Re: z home switch
Post by: Tweakie.CNC on August 10, 2011, 05:57:44 AM

Hi Chieffy,

It could be switch bounce. Try increasing the Debounce Interval in Config / General Config and see if that helps.

Tweakie.

Title: Re: z home switch
Post by: Chieffy on August 10, 2011, 01:57:11 PM

Hello Tweakie:

Thanks for your help will try this as soon as I get home.

Thanks!!

Title: Re: z home switch
Post by: Chieffy on August 11, 2011, 05:06:22 PM

Hi Tweakie:

Tried it last night and it worked. No idea what it does but for now that is fine as long as it works,lol.

Thanks again

Chieffy

Title: Re: z home switch
Post by: Tweakie.CNC on August 12, 2011, 02:01:34 AM

Hi Chieffy,

I am pleased you have it working OK now.

Basically the switch contacts bounce, making and breaking contact many times and the software thinks the machine has backed off the switch when in fact it hasn't. The Debounce delay has been incorporated within Mach to take care of just this situation.

Personally, I would doubt the quality of the particular switch that caused the issue and perhaps replace it with one of better pedigree as soon as I could.  ;)

Tweakie.