Trogan,
Use a
[email protected] A to power the board. This goes in the main power connection, the one on the end of the boards with two sets of +5vdc and GND terminals. This is what powers the board. The other power terminal is optional, is for powering the outputs circuit in case you need to keep the isolated. Most drivers are optoisolated, but if using the G320, you need the optoisolation as the ERR/RES terminal is not optoisolated. The +12vdc terminal is just for the analog circuit. If using a VFD, you can power this with the +10vdc reference from the VFD.
Let me know is clear enough.
Arturo Duncan
:: CNC4PC :: iNtRo