Siemens SINUMERIK 840D Function Manual page 79

The following rules apply to making manual fine adjustments:
Monitoring
Overshoot
Excessively slow
approach
Note
The effects are similar to modification of the position controller gain (MD32200
$MA_POSCTRL_GAIN). They can be observed on the user interface in the operating section
"Diagnostics" > "Axis service" using the computed K
MD32810 fine adjustment
Therefore, MD32810 should be assigned as small a value as possible, with the overshoot
setting the limit during positioning. Furthermore, the initial value is only modified slightly during
fine adjustment, typically by adding or deducting 0.25 ms.
For example, if the initial value is 1.5 ms, the optimum value calculated manually is usually
within the range 1.25 ms to 1.75 ms.
In the case of axes equipped with direct measuring systems (load encoders) and strong
elasticity, you may possibly accept small overshoots of some micrometers. These can be
reduced with the help of the position setpoint filter for dynamic response adaptation (MD32910
$MA_DYN_MATCH_TIME) and for jerk (MD32410 $MA_AX_JERK_TIME), which also reduces
the axis speed.
Identical axis data within an interpolation group
All the axes within an interpolation group should have identical settings in the following data:
● MD32200 $MA_POSCTRL_GAIN (adapted using MD32910)
● MD32620 $MA_FFW_MODE
● MD32610 $MA_VELO_FFW_WEIGHT
● MD32810 $MA_EQUIV_SPEEDCTRL_TIME (or MD32800
$MA_EQUIV_CURRCTRL_TIME) (dependent on the mechanical system and drive)
● MD32400 $MA_AX_JERK_ENABLE
● MD32402 $MA_AX_JERK_MODE
● MD32410 $MA_AX_JERK_TIME
The servo gain display (K
service" is used for checking.
Non-identical axis data within an interpolation group
If identical values are not possible for the above data, the following machine data can be used
to make an adjustment:
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA
G2: Velocities, setpoint / actual value systems, closed-loop control
Measure
Increase MD32810
Reduce MD32810
) of the user interface in operating section "Diagnostics" > "Axis
V
2.6 Optimization of the control
Effect
The position controller responds more slowly.
⇒ The tendency to overshoot decreases.
Problem: The contour error (deviation from the program‐
med contour) increases at curves.
The position controller responds faster.
⇒ The contour error at curves decreases.
Problem: The tendency to overshoot increases.
value.
V
79