. .

Threaded View

Previous Post Previous Post   Next Post Next Post
  1. #14
    Quote Originally Posted by Danielroyal25 View Post
    If I use separate home switches for x,y,z & x2 linked directly to the bob
    Ok first Not sure what your meaning here Dan with x2.? You only have 1 home switch per axis.

    Quote Originally Posted by Danielroyal25 View Post
    then have my individual limit switches + and - for x,y & z linked via the 24v circuit, where are the home switches to be positioned?
    Originally I was going to use the home switches to act as limits on one end and have limit switches on the other but if I go for the setup above I'm confused as to where the homes should be placed.
    Ok well if using Micro switch type then you still have the LIMIT switches at the ends, so 2 switches per axis.
    The home switches are normally positioned just before the limit switches and so they home to a corner or end you would like to designate Zero position in Machine coordinates. That said they can be positioned anywhere you like really.!!
    Personally I set my machines up so they home to corner then all my moves are always positive in machine coordinates. Mach is then setup to always home negative, this way it can't ever home in the wrong direction.

    Now to answer the question of how do you put a home switch before limit switch.? It's easy really.!! . . . . You position The switch so gets triggered by a ride over Ramp not a hard stop. The ramp allows the switch to ride over while cutting and still have access to Limit switches at the ends. (Thou better other way round so static switch with mobile ramp triggering.!)
    Home switch inputs are only watched or checked while homing so when it rides over the ramp it triggers, rest of time it's ignored.
    This does mean the Home switches need an input of there own, they can still be wired in series but separate input to limits.

    This is the reason why you can use Limit switches has home switches if sharing the same input or switch because the opposite is true while homing.!. . Limit's are ignored.
    So if set to do this Mach treats the input differently while homing and instead of seeing the switch trigger and setting E-stop condition it now sets the current position has Zero Machine coordinate and resets Axis DRO's to zero.

    Really micro switch type switches are not the best for Home switches unless very high quality due to them not being very repeatable. MS are fine for limits has they just work has ON/OFF triggers.
    Inductive proximity switches or hall affect switches are better being much more accurate/repeatable and with contact less operation so they work without ramps etc.

    Hope this helps clear it bit more.!

  2. The Following User Says Thank You to JAZZCNC For This Useful Post:


Thread Information

Users Browsing this Thread

There are currently 5 users browsing this thread. (0 members and 5 guests)

Similar Threads

  1. EMC2 home/limit switches... only acting as limit?
    By vputz in forum LinuxCNC (EMC)
    Replies: 4
    Last Post: 15-10-2014, 09:51 AM
  2. 24v Limit/Home switches. How to..?
    By Wal in forum General Electronics
    Replies: 6
    Last Post: 17-11-2013, 05:52 PM
  3. Limit Switches with LED's
    By manofgresley in forum General Electronics
    Replies: 30
    Last Post: 02-01-2013, 03:08 PM
  4. Limit/home switches - how are you mounting 'em?
    By HankMcSpank in forum General Discussion
    Replies: 2
    Last Post: 13-11-2011, 01:42 PM
  5. The best solution for limit / home switches on a mill is .....what ?
    By NICKMODELMAKER in forum Gantry/Router Machines & Building
    Replies: 1
    Last Post: 29-05-2010, 01:38 PM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •