Welcome to Our Community

Some features disabled for guests. Register Today.

Help With Installing Limit Switches to Chinese GRBL 0.9j

Discussion in 'CNC Mills/Routers' started by 1759adam, Jun 16, 2019.

  1. 1759adam

    1759adam New
    Builder

    Joined:
    Jun 16, 2019
    Messages:
    4
    Likes Received:
    0
    New to the forum and I've just completed assembly and modification of a Chinese CNC Router.

    I have limit switches mounted now on 2 on X, 2 on Y and 1 on the top of Z, but I can't figure out how to wire them to my Chinese 0.9j GRBL board.

    I have looked at many diagrams for wiring in series, but my GRBL Board has 3 pins on each of the X,Y and Z limit inputs. These are marked + - and S on the backside of board.

    Can anyone suggest how I should wire a Normally Closed circuit to this with my 5 Micro Switches, please.....?

    Image of mystery board attached with Limit Pins to the right of image.

    Many thanks in advance,

    Adam Chinese GRBL 0.9 Board.jpg
     
  2. Giarc

    Giarc OpenBuilds Team
    Staff Member Moderator Builder Resident Builder

    Joined:
    Jan 24, 2015
    Messages:
    2,899
    Likes Received:
    1,613
    I am not familiar with that board. Have you tried the manufacturer's customer service yet? They may be in the best position to help you.
     
    1759adam likes this.
  3. Christian James

    Christian James Journeyman
    Builder

    Joined:
    Jun 8, 2018
    Messages:
    434
    Likes Received:
    210
    I don't know that board either but the 3rd input pin (S) must be the signal pin and would be used together with the +/- pins for an optical sensor connection. If you are using micro-switches however, then just use the S and ground (-) pin, the "S" to "normally closed" on the switch and ground to "C" on the switch.
    Just do not wire it wrong ( keep away from the + pin - that's for the optical sensor)

    Have a look here at the series and parallel switch wiring..

    gnea/grbl
     
    #3 Christian James, Jun 18, 2019
    Last edited: Jun 18, 2019
    1759adam likes this.
  4. 1759adam

    1759adam New
    Builder

    Joined:
    Jun 16, 2019
    Messages:
    4
    Likes Received:
    0
    Thanks for replies. I'll get to work. Regards,
    Adam
     
  5. 1759adam

    1759adam New
    Builder

    Joined:
    Jun 16, 2019
    Messages:
    4
    Likes Received:
    0
    Thanks for your advice. I've connected 1 micro-switch as you suggested and it's now working. To get left and right limits on X Axis, should I connect Micro-Switches together via COM pins, and to -, and wire both NC pins together into S on the board?

    Many thanks,

    Adam
     
  6. Alex Chambers

    Alex Chambers Master
    Moderator Builder

    Joined:
    Nov 1, 2018
    Messages:
    2,681
    Likes Received:
    1,321
    For Normally Closed switches you need to wire two switches on the same axis in series - signal (control board) to nc (switch one), common (switch one) to nc (switch two), common (switch two) to ground (control board)
    Alex.
     
    1759adam likes this.
  7. 1759adam

    1759adam New
    Builder

    Joined:
    Jun 16, 2019
    Messages:
    4
    Likes Received:
    0
    Many thanks, I was about to ask if this diagram is correct, but I think you have already described.
     

    Attached Files:

  8. Christian James

    Christian James Journeyman
    Builder

    Joined:
    Jun 8, 2018
    Messages:
    434
    Likes Received:
    210
    Here's another drawing attached cnc_limit_switch_c3.png
     
    Alex Chambers likes this.
  9. Alex Chambers

    Alex Chambers Master
    Moderator Builder

    Joined:
    Nov 1, 2018
    Messages:
    2,681
    Likes Received:
    1,321
    Bear in mind however that is for normally open limit switches.
    Alex.
     
  10. Christian James

    Christian James Journeyman
    Builder

    Joined:
    Jun 8, 2018
    Messages:
    434
    Likes Received:
    210
    Yes Alex, and I believe pin 12 should be used and not pin 11.
     
  11. Alex Chambers

    Alex Chambers Master
    Moderator Builder

    Joined:
    Nov 1, 2018
    Messages:
    2,681
    Likes Received:
    1,321
    Can't help with that one @Christian James, but hopefully someone who is familiar with that set-up will clarify that before someone tries to use that diagram. I think @sharmstr has used an arduino and may be able to help.
    Alex.
     
  12. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
    Staff Member Moderator Builder Resident Builder

    Joined:
    Mar 1, 2017
    Messages:
    13,753
    Likes Received:
    4,070
    Refer to the Grbl wiki for all the pin information gnea/grbl
     
  13. Christian James

    Christian James Journeyman
    Builder

    Joined:
    Jun 8, 2018
    Messages:
    434
    Likes Received:
    210
    Yes Peter, that confirms what I thought and how mine is wired. Pin 11 has been grabbed for use by the spindle while the Z switch pin has been shoved onto pin 12
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice