Quote Originally Posted by dachopper View Post
How are guys doing this? just Cutting the Active line before the ac/dc converter using a low voltage DC press button through a relay?
My machine uses dual motors/ballscrews on X axis, driven by EM806 (very similar to 882), so I'm a bit paranoid about stopping everything if one of the motors stalls to avoid tearing the gantry apart. To do this, I've wired the fault outputs of drivers in series with e-stop switches (all three of them) so hitting e-stop or fault signal from any driver do the same thing. I also use a safety relay with latching function. Relay is energised by momentary action switch and will drop out on e-stop or fault. Safety relay contacts (a) cut power to second relay which removes a.c. power from driver power supply, (b) cut enable signal to drivers, (c) send signal to motion controller e-stop input (I'm using CSMIO IP/M). So on fault, driver loses power so resetting safety relay (front panel push button) will reapply power and reset driver. So far, all driver faults have been motor stall, when I was trying to drive X a bit too fast. Dropped max rapid speed for X and it's been fine since.

It all depends on your paranoia quotient, but with a largely unattended machine I would probably do something similar - safety relay does the basic "stop everything" actions while the motion controller does other bits and pieces in the background, but I don't rely on it for primary safety. Downside, maybe, is that you have to hit front panel button as well as reset button in Mach3 to restart but that's not a big deal.

One man's view - I'm sure others will do it differently.