06.03
13.4 Frequency response measurement
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Siemens AG, 2003. All rights reserved
SINUMERIK 840Di Manual (HBI) – 06.03 Edition
Speed
Amplitude
Offset
Settling time
Measuring period
t
t
0
0
Position
Ramp
time
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!
Step height
13 Drive Optimization using HMI Advanced
