I have 2 wire limit switches. com=black wire. As far as the red wire which i have going to NO, does this wire go to the sig. on the black box? In my research it looks like it does but just want to confirm that it does not go to voltage on the box. Also when it comes to stepper motors, Does it matter which side of the frame it is mounted to? I have mine mounted to the left side facing front and in videos I see it is mounted on the right side. Do I need to change any wire matching in this case going to the black box? Thank you for any help.
GRD and SIG are correct. V+ is for the limit switches with LEDs You can put the motor on any side you want. When you get it hooked up, jog the machine in the X+ direction. If it moves X- (the wrong direction) you can invert the direction by changing $3 in grbl. Easy to do if you are using OB Control. Just go into the troubleshooting tab, click on "Invert X Direction", click the Save to Firmware icon and you should be set.
On your limit/home switches, it doesn't really matter which pins of the switches go to the input pins (Gnd and Sig). However, if you are using shielded wire (a good idea), the shield needs to connect to Gnd on the controller. Finally, you might want to consider using your limit switches NC instead of NO. NO is more susceptible to glitches.
gnea/grbl has the more advanced diagrams. NO works 99% of the time though, unless you have a VFD or Plasma or some other non standard source of EMI around (; Of course if EMI worries you, rather invest in a couple of Xtension Limit Switch Kit - onboard EMI filtering and indicator LED (;
Since there is no cost for wiring NC vs NO, why not NC? Seems like a prudent choice. I have gotten false triggers on a pause switch that was NO - no VFD or such. Also, I regularly had an issue with turning on the power supply and it would cause noise on the USB line requiring me to power cycle my GRBL board. Using a ferrite on the USB cord fixed that.
I am going to be running a VFD, So I am just going to order the Xtension limit switches. With these switches I will not have to worry about NO or NC? Should this take care of any interference concerns? Thank you for your help.
