The steps Per setting is not something you can guess or what sets the Rapid speed. It's an exact number which ensures you move the correct distance for one unit of measurement derived from calculation of the Encoder Resolution divided by the distance traveled for Revolution.

So if your Encoders are 2500ppr and they are quadrature this number becomes 2500 x 4 =10,000ppr. And your using Ballscrews with 10mm pitch connected directly to the motors. Then the steps per setting would be 10,000 / 10 = 1000 Steps per.

However if your using a Ratio to connect screws to motor, which with servos you probably will be doing then calculation gets a little more involved. See the Mach manual and it will explain how to calculate this depending on your setup.