Siemens SINUMERIK 840D sl Function Manual page 444

Detailed description
2.3 Setpoint /actual-value system
Rotary axis with rotary encoder on motor
Figure 2-9
In order to adapt the actual-value resolution to the calculation resolution, the control
calculates the quotients from the "internal increments/degree" and the "encoder
increments/degree" as follows:
Example for rotary axis with encoder on motor
Rotary axis with rotary encoder (2048 Impulse) on motor;
internal multiplication (2048)
Gear:
56
Rotary axis with rotary encoder on motor
Motor/rotary axis 5
1000 increments per degree
Basic logic functions: Velocities, Setpoint/Actual Value Systems, Closed-Loop Control (G2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0