Well I've finally made a start after collecting "The Bits".
Anyways I'd thought I'd do it back to front and get the electronics sorted then get onto the mechanical side. Reason being the electronics I can get locally, the mechanical bits have to come from Overseas.
The electronics are going to be contained in 2 19" rack enclosures, a 3U one for the stepper drives & PS and a 2U for the BOB and other sundry logic. The stepper box is complete and functioning (all wired up correctly 1st time) and now I'm thinking about the E-Stop.
Do I or should I on a E-Stop condition
- Cut power to the mains supply and have a 1 to 2 second delay in shutting power to the stepper drives due to the PS caps discharging.
- Cut the 48V rail to the drives via relays and leave the mains untouched. I do have a power switch to turn off the mains.
- Use a couple of relays to disconnect the Step signal to the drivers. Thereby leaving the steppers in a "held state".
Personally I'm tending toward the second option as I can wire up a relay and a pushbutton as a NVR switch on the 48v rail. The E-Stop will do any disabling of equipment and will just inform Mach of the E-Stop condition.
If this seems a bit confusing I can post up some pictures\diagrams in the morning.
Cheers
Rob