Zero level setting and calibration of roller in the compression machine

How zero level setting and calibration of roller is performed in the compression machine and why it is required.

Reduce the overload pressure to zero.
Reduce the hardness of both the side to zero.
Now for the set weight of tablet the machine , the speed of the machine is reduced to minimum
Inch the machine.Both side should give granules at ejection.
If so that indicates the pressure rollers of both side and top and bottom are having equal diameter and are in good condition
The said exercise is essential for smooth operation and reducing wear and year of moving parts of machine.