Siemens SINUMERIK 840Di Manual page 430

13 Drive Optimization using HMI Advanced
13.4 Frequency response measurement
Step height
13-430
Position
Amplitude
0
Settling time
Speed
Offset
0
Fig. 13-5 Signal curve with measuring function position setpoint/ramp
At maximum axis velocity, there is a (virtual) step change in the velocity (contin-
uous line).
The curves represented by the dashed line correspond to a realistic, finite
value. The offset component is excluded from the display graphic in order to
emphasize the transient processes.
In order to avoid damage to the machine, the step height for the setpoint step
change is limited to the value specified in
S
MD 32000 MAX_AX_VELO (maximum axis velocity).
This can lead to not achieving the desired step height.
Just as well, the
S
MD 32000 MAX_AX_VELO (maximum axis velocity)
S
MD 32300 MAX_AX_ACCEL (max. axis acceleration)
are effective with the setpoint ramp in the range of the ramp. The max. axis ve-
locity limits the ramp rate of rise (velocity limitation) whereby the drive does not
reach the programmed end position (amplitude).
The acceleration limitation caused by the max. acceleration "rounds" the transi-
tion at the beginning and end of the ramp.
Caution
Changing:
S
MD 32000 MAX_AX_VELO (maximum axis velocity).
S
MD 32300 MAX_AX_ACCEL (max. axis acceleration)
may only be carried out with utmost care, e.g. by a certain step height. These
machine data are exactly matched with the machine!
Ramp Measuring period
time
 Siemens AG, 2003. All rights reserved
SINUMERIK 840Di Manual (HBI) – 06.03 Edition
06.03
t
t