gecko 320 filter capacitor values

Hi all,
I'm looking for advice on sizing power supply filter capacitors for Gecko 320
servo drives, used to power 2 separate servo applications.
First application is for 1 servo motor rated with these specs:
terminal voltage: 72 VDC continuous current: 8.5A peak current: 38A. How
large should the filter capacitor be? Would a 100VDC rating be sufficient for
this 72 volt supply? How many MFD?
Second application is for 2 motors with these ratings:
terminal voltage 60 VDC continuous current 3.5A peak current 20A. Would a
75 VDC capacitor be sufficient for this 60 VDC supply? How many MFD?
Is there a formula that is available to calculate the mfd value?
Is there a recommended maximum ripple voltage?
cheers,
Denis