Quote Originally Posted by JAZZCNC View Post
Don't Agree but Know what your saying. Hitting the limits isn't really an emergency it's a machine positional error and no different from missed steps which you wouldn't hit the E-stop for, or should say want to Kill power for.
Really it comes down to how you want to stop the machine if some thing goes wrong, that could be a serious situation or just because you see something like it's going to hit a clamp etc.? There's several ways to look at it.!

When it's Minor then you just want to Halt the machine movement so Feed hold is best, you don't always want the Spindle or Coolant, Vacuum etc to go Off. This could be the case with the Limits has it's only lost position why would you want the spindle off or Vacuum.? Turning the spindle off could damage the tool if it's still in the material, same goes for vacuum no need for it off.
Soooo, should the limit switches be in series with the E-Stops or not? I've essentially got 2 mains supplies - one direct to the PC, Monitor, 24V PSU, etc and one switched through the safety contactor. When a safety switch is activated, it kills the power to the 42V steppers PSU. I haven't fitted the spindle VFD yet, but it will use the "safe" supply as I'll want the spindle to stop when I hit an E-Stop. But with the limits in series, an overshoot will also cause an emergency stop. Is there a better way of doing this? I don't want to rely on software to handle E-Stops.