GRBLDuino Uno 3 Wire Limit Switch Connection?
Posted: Sun Feb 09, 2020 4:16 pm
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.
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.
- GRBLDuino Uno 3 Wire Limit Switch Connection
- 3 Wire Limit Switch Connection.png (128.98 KiB) Viewed 4048 times
- GRBLDuino Uno 3 Wire Limit Switch Connection
- 3 Wire Limit Switch Connection.png (128.98 KiB) Viewed 4048 times