Welcome, Guest. Please login or register.
Did you miss your activation email?
May 25, 2012, 07:27:50 AM

Login with username, password and session length
Search:     Advanced search
* Home Help Search Calendar Links Login Register
+  Machsupport Forum
|-+  Third party software and hardware support forums.
| |-+  SmoothStepper USB (Moderator: Warp9TD)
| | |-+  Overrun Limits Using SS
Pages: 1   Go Down
Print
Author Topic: Overrun Limits Using SS  (Read 903 times)
0 Members and 2 Guests are viewing this topic.
Kently
Active Member

Offline Offline

Posts: 60


View Profile
« on: August 31, 2009, 10:42:09 AM »

I am using hall effect sensors for my limit switches. I use a small button magnet and thus the limit switch is only activated over a short range. If the axis is moving fast you will get a short duration pulse out of the limit switch. It appears that the duration is not long enough for the SmoothStepper to register the limit and thus I can run right past the limit switch. I am not sure at what speed it will work, but I know I have overrun it at 300 ipm.  Slow speed operation, such as when I am homing, works fine. Has anyone else experienced this?
Logged
Cruiser
Active Member

Offline Offline

Posts: 107


View Profile
« Reply #1 on: August 31, 2009, 11:17:07 AM »

Hall sensors are used for ignition triggers on Radio controlled gas engines and I use them plenty ! What I've found is that they have a low voltage threshold and will not trigger reliably if voltage is not hot enough. Also, the magnet has to be strong enough to make the trigger. I'd test the voltage supply to the hall switch and also test that the magnet is still viable. It should be able to trigger well above 40,000 " min ! That comes from a 2" hub turning at close to 7,000 rpm !
Logged

CRUISER
  Don
Jeff_Birt
Active Member

Offline Offline

Posts: 809




View Profile WWW
« Reply #2 on: August 31, 2009, 11:20:24 AM »

There is a recently discovered problem in the SS plug-in. Mach had a setting called 'Disable Limits' that is no longer used or accessible by the user, but defaults to 'ON' (which is bad). This is causing the SS to not treat a limit as a limit but rather just decelerate the motor to a stop (hence the over run). Greg is working on it now.
Logged

Happy machining , Jeff Birt
 
Cruiser
Active Member

Offline Offline

Posts: 107


View Profile
« Reply #3 on: August 31, 2009, 11:23:44 AM »

OOPS ! I missed the SS part ! or I would have added that too ! This is the recent HOT thread on the OTHER site.
Logged

CRUISER
  Don
Pages: 1   Go Up
Print
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.16 | SMF © 2011, Simple Machines Valid XHTML 1.0! Valid CSS!