GRBLDuino Uno 3 Wire Limit Switch Connection?

Use, set up, assembly help, and any other GRBLDuino related questions or comments.
Post Reply
User avatar
EccentricWorkshop
Admin
Posts: 37
Joined: Thu Jan 17, 2019 9:33 pm
Location: Olympia, WA
Contact:

GRBLDuino Uno 3 Wire Limit Switch Connection?

#1

Post by EccentricWorkshop »

I'm not super familiar with 3 wire limit switches so this is a little bit speculation and will require a bit of experimentation. The switches have Signal, V+, and GND.

The hard part will be getting 5v - it'll require soldering a wire to the 5v pin on the shield (5th pin from the left on the bottom front pin header, right above the last - in the spindle label). The signal for each axis will go into the bottom terminal for each pair which is also the one closest to the axis label (X, Y, or Z rather than Lim). The other terminal is connected to the limit select jumper.

Here's a thought though, if the probe connection is not in use, the GND lines could be connected to the right terminal (closest to the X+ Lim) as that is GND, and set Lim.H/L to H and get 5v from the non-signal terminal from each limit switch terminal block.
3 Wire Limit Switch Connection.png
GRBLDuino Uno 3 Wire Limit Switch Connection
3 Wire Limit Switch Connection.png (128.98 KiB) Viewed 2117 times
GRBLDuino Uno 3 Wire Limit Switch Connection
GRBLDuino Uno 3 Wire Limit Switch Connection
3 Wire Limit Switch Connection.png (128.98 KiB) Viewed 2117 times
--------------------
Andy
Eccentric Workshop
Store - Tindie - eBay
Kenoctech
Posts: 2
Joined: Sun Feb 09, 2020 7:33 pm

Re: GRBLDuino Uno 3 Wire Limit Switch Connection?

#2

Post by Kenoctech »

Thanks for these instructions! This should help for those of us trying to use 3 connector switches like this one from OpenBuilds: https://openbuildspartstore.com/micro-limit-switch-kit/

Plus endstops that have an indicator LED.
Post Reply