Siemens SINUMERIK 828D Commissioning Manual page 203

The following machine data is first checked and set:
● MD32200 $MA_POSCTRL_GAIN = 0
● MD32610 $MA_VELO_FFW_WEIGHT = 1
● MD32620 $MA_FFW_MODE = 3
● MD32810 $MA_EQUIV_SPEEDCTRL_TIME = as tuned
The following examples show the effects of different jerk values on the positioning of an axis.
Examples
The MD32431 axis machine data is used to set the jerk.
Example 1: MD32431 $MA_MAX_AX_JERK = 600 ⇒ jerk too high.
1. Restart the trace and then execute the part program.
2. Press the "Start trace" softkey and then the <RESET> and <CYCLE START> keys.
3. Correct the overshoot by increasing MAX_AX_JERK.
This diagram shows the jerk increase until an overshoot caused by the mechanical system.
Example 2: MD32431 $MA_MAX_AX_JERK = 2 ⇒ jerk too low.
A jerk that is too low causes the positioning contour to be rounded.
Example 3: MD32431 $MA_MAX_AX_JERK = 65 ⇒ jerk tuned.
If the jerk is tuned, there is no overshoot or it is small and the positioning contour is sharp.
CNC commissioning
Commissioning Manual, 10/2015, 6FC5397-3DP40-5BA3
Tuning
6.3 Optimizing the axis jerk
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