Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: tylerthejet on July 01, 2009, 08:34:03 AM

Title: Bouncing Z axis
Post by: tylerthejet on July 01, 2009, 08:34:03 AM
Hey,

I am trying to home my z axis on my positive limit switch, but for some reason when it hits the switch, the instant it moves off it goes right back up again into the switch.  I left it for a minute or two and it continued to bounce on and off the limit switch with no signs of slowing down or stopping.  The thing that gets me is that when I home on the negative z lim switch, it works perfectly.  None of the other limit switches are behaving this way either, only the z+.  I would say that it is almost like it is looping the homing function for z.  Also, the Reset button on Mach doesn't stop it. I need to turn the servo off, cut the power or close Mach altogether. 

Has anyone else had this problem?

Regards,
Tyler
Title: Re: Bouncing Z axis
Post by: Hood on July 01, 2009, 04:41:40 PM
Can you attach your xml please.
Hood
Title: Re: Bouncing Z axis
Post by: tylerthejet on July 02, 2009, 09:32:08 AM
Hey Hood,

Here is my xml file.
Title: Re: Bouncing Z axis
Post by: Hood on July 02, 2009, 02:58:18 PM
Have you tried using a different screenset as a test?
Hood
Title: Re: Bouncing Z axis
Post by: tylerthejet on July 07, 2009, 05:08:23 PM
Sorry about the long reply.
I tried using the original screenset and the same thing happened.  It only stops if Mach3 is turned off or if the power is cut.  So, everything else looked fine in the xml?

Regards,
Tyler
Title: Re: Bouncing Z axis
Post by: tylerthejet on July 08, 2009, 11:19:30 AM
I've attached a short clip of what it does. Strange eh? 
Title: Re: Bouncing Z axis
Post by: Hood on July 09, 2009, 02:06:42 AM
Sorry, I have  not been here much last few days.
 If I recall your xml looked fine. Just looked at the vid and have never seen anything like that before. How have you got the limit connected, does it go to Mach or does it go to your servo drive?
 Have you tried referencing that axis seperately?
Hood
Title: Re: Bouncing Z axis
Post by: tylerthejet on July 13, 2009, 08:18:18 AM
Hey,

My limit switches go to a relay board where it splits and goes to Mach and to my servo.  Yeah, I've tried referencing my z separately.  I might just have to home to  my other switch and deal with it.  Thanks.

Tyler
Title: Re: Bouncing Z axis
Post by: Hood on July 13, 2009, 08:51:31 AM
What I would do as a test is go to your Home switch in Ports and Pins and set up a keyboard key for emulation. Then start the homing and press that keyboard key and keep it pressed and see if the axis stops and then starts backing off then when you relaease the keyboard key see if it stops. You will need to do this before it reaches the real limit switch so that it is taken out of the equation. If that works then I suspect your servo drive has some sort of limit or homing routine internally and we can cross that bridge when we get to it.

Hood
Title: Re: Bouncing Z axis
Post by: tylerthejet on July 18, 2009, 10:43:14 AM
Hey,

I emulated my homing for my z axis using the "Home" key, and it worked perfectly.  I will re-check the settings for my servo and see how it compares to my other axis' that are working. 

Tyler