by yonghui » Fri Nov 05, 2010 9:39 pm
hi,
the boards supply is always shared together from the power card, the communications need common ground. but for the motors u can use separate supply, not necessary the supply from power card. just connect the cable of the motor supply to ur own supply. check for the schematic of th board. using the power card actually provides some advantages in term of the overload, and reverse polarity protection.
regards,
yh
thanks®ards,
yh