Siemens SINUMERIK 840D sl Function Manual page 443

Linear axis with rotary encoder on the machine
Figure 2-8
In order to adapt the actual-value resolution to the calculation resolution, the control
calculates the quotients from the "internal increments/mm" and the "encoder increments/mm"
as follows:
Basic logic functions: Velocities, Setpoint/Actual Value Systems, Closed-Loop Control (G2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Linear axis with rotary encoder on the machine
Detailed description
2.3 Setpoint /actual-value system
55