do i need a large capacitor?

Hi All,

I am finally getting all my pieces together. I have a Xylotex driver
board, powermax II steppers, and a 28V 6A linear power supply.

There are two 10 000uF/50V caps in parallel in the power supply.
Do I require another cap because I plan to run the system at 28
volts, which is close to the 35V max for the Xylotex.

Thanks in advnce,

Les