E-STOP Circuit - will this cause any problems?

[birchy]

I would not like a fault on the machine control side to trip the mcb and dump the pc at the same time.

Fair point and easy to change.

Don't see any limit switch's. . . Are you not using them.?

Ermmmm...good question! I presume you mean limit switches to prevent the X, Y, Z from trying to drive beyond their physical stops? Although I've considered them, I was thinking that the stops can be set within the software, and if something went wrong, the drives would trip on overcurrent protection? Should limit switches REALLY be wired into the Safety Circuit? It seems wrong to me as they should be part of the machine functionality rather than an Emergency or Safety device?