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Mach Discussion => General Mach Discussion => Topic started by: natefoerg on January 21, 2014, 10:45:39 AM

Title: My X home switch is not backing off after homing this axis.
Post by: natefoerg on January 21, 2014, 10:45:39 AM
The Y axis still homes and backs off, but the X axis only homes, does not back off the switch any more.

What might cause this. Note, I have not made any changes, this just started happening.

XML posted in this thread (forum prevents posting same twice) http://www.machsupport.com/forum/index.php/topic,26374.new.html#new

Thanks!
Title: Re: My X home switch is not backing off after homing this axis.
Post by: ger21 on January 21, 2014, 10:48:37 AM
Is there an error message? Is the axis "Ref'd" after it hits the switch? It's only supposed to back up enough for the switch to open.
Title: Re: My X home switch is not backing off after homing this axis.
Post by: natefoerg on January 21, 2014, 12:20:16 PM
The error message only pops up if I attempt to home it again after doing the homing once. The error message is something to the effect of- limit switch is activated, please deactivate limit switch before homing machine.

The only reason I found that it is not moving off the X axis home switch is that you can hear it move off the Y switch, and I did not hear it move off the X switch. Sure enough, when looking at the switch , the x axis does not preform the move off of it.

Any thoughts?
Title: Re: My X home switch is not backing off after homing this axis.
Post by: ger21 on January 21, 2014, 12:55:33 PM
Does the Ref LED light up?
Title: Re: My X home switch is not backing off after homing this axis.
Post by: natefoerg on January 21, 2014, 12:58:47 PM
Is the ref led the box around the X, Y, Z, or 4 that turns green? (on the program run page)
Title: Re: My X home switch is not backing off after homing this axis.
Post by: ger21 on January 21, 2014, 01:09:04 PM
yes
Title: Re: My X home switch is not backing off after homing this axis.
Post by: natefoerg on January 21, 2014, 01:12:38 PM
I am not in front of it, but I remember that the Y RefLED will turn green and the X RefLED does not.

So, does that mean it is not completing homing the X even though it is tripping the switch? I know the switch is being activated as it stops at it and the M1Home and M2Home leds on the diagnostics page are both lit after homing.

Title: Re: My X home switch is not backing off after homing this axis.
Post by: natefoerg on January 21, 2014, 05:32:56 PM
I take it back. The ref leds indeed do turn green, both Y and X.
Title: Re: My X home switch is not backing off after homing this axis.
Post by: Picengraver on January 21, 2014, 07:47:46 PM
A bad switch (contact bounce)?  Try changing it.
John Champlain
Title: Re: My X home switch is not backing off after homing this axis.
Post by: ger21 on January 21, 2014, 08:59:43 PM
Yes, it sounds like the switches is opening and closing again.
Title: Re: My X home switch is not backing off after homing this axis.
Post by: natefoerg on January 21, 2014, 10:11:45 PM
I replaced the switch with an identical one. These are very expensive Square D push roller style switches.

Same problem. Actually, when I tested the new switch by temp soldering it it worked again, when I perm soldered and heat shrunk, same issue...

Tried debounce of 200.

I dont get it.
Title: Re: My X home switch is not backing off after homing this axis.
Post by: Overloaded on January 21, 2014, 11:54:37 PM
You might try a de-bounce of 1000. (or more)
Be sure the homing speed is relatively slow to avoid a crash.
Might prove, or disprove a raggedy switch.
Is the mounting rigid and vibration free ?
Possibilities ?
Russ
Title: Re: My X home switch is not backing off after homing this axis.
Post by: natefoerg on January 22, 2014, 10:22:15 AM
Well, it turns out that I was not actually adjusting the debounce right.

I was in the SS page, but was changing the debounce for LIMITS, not HOME. Once I changed the HOME debounce, the problem dissapeared....

Thanks everyone!
Title: Re: My X home switch is not backing off after homing this axis.
Post by: ger21 on January 22, 2014, 11:06:16 AM
This goes for everyone reading this. When you post a question, and you're not using the parallel port, then please be sure to specify the motion device your using. It usually makes a big difference in answering the question.