Basically what Phil said is sound - check the support documentation on this site.
You do no say what motors you are using, what steppers you are using or what gearing you are using on your set up. To give you an idea of mine - then you may get an idea where you have gone wrong - look in Config/Motor Tuning.
The first question is "steps per unit". This is a misleading term. It should be pulses per unit.
My motors are 1.8 degree - 200 steps per rev. My drivers are Gecko, which put out 10 microsteps per step - therefore I need 2000 pulses to turn the motors one rev. These are connected via a 3 to 1 reduction gear to my lathe main shaft - 6000 pulses per rev.
My mainshaft needs to turn 10 times to move the saddle 1 inch. 60,000 pulses.
Therefore if your machine follows along those lines - your pulses (or steps) per unit (assuming inches) - should be well above the 3200 you are quoting.
We then get on to inches per minute movement of your saddle/table. This also is entered into the Motor tuning page (do not foget to save each axis as you complete it) If you want your axis to move at say 20 or even 40 inches per minute (remember this is fast speed - not cutting speed) - then set the speed at that and the acceleration at say 1 or 2. You may even want the table to move faster - but I would wait til you get it all connected up before you get into that.
Finally you can jog - if you use Mach 3 mill you jog at full speed, lathe - there is a percentage figure that you can change - put it up to 100% - I dont know if the plasma screens have any adjustment.
You should find that the motors now turn in a fair representation of the speed they should move on your machine. You can fine tune them to get higher speeds out of them, and adjust the acceleration to get the best response. The number of "pulses" per unit is however, fixed, and should be calculated accurately.