Siemens SINUMERIK 840DiE sl Manual page 439

01/2007
Measurement:
Setpoint step
change
Measurement:
Setpoint ramp
© Siemens AG 2007 All Rights Reserved
SINUMERIK 840Di sl Manual (HBIsl) – 01/2007 Edition
Position
Amplitude
0
Settling time
Speed controller
Offset
0
Fig. 14-4 Signal chart for position setpoint/ramp measuring function
At maximum axis velocity, there is a (virtual) step change in the velocity
(continuous 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.
To avoid overloading the mechanical system of the machine, the step height is
limited to the value specified in the machine data during the "Setpoint step
change" measurement:
S
MD 32000 MAX_AX_VELO (maximum axis velocity)
This may result in failure to achieve the desired step height.
With measurement: "Setpoint ramp", the following machine data influence the
measurement result:
S
MD 32000 MAX_AX_VELO (max. axis velocity)
The maximum axis velocity limits the ramp slope (velocity limiter). The drive
does not reach the programmed end position (amplitude).
S
MD 32300 MAX_AX_ACCEL (max. axis acceleration)
The maximum axis acceleration limits the change in speed (acceleration
limiter). This leads to "rounding" on the transitions at the beginning and end
of the ramp.
Caution
In normal cases the machine data correspond exactly with the load capacity of
the machine kinematics and should not be changed (increased) as part of the
measurements:
S
MD 32000 MAX_AX_VELO (maximum axis velocity)
S
MD 32300 MAX_AX_ACCEL (max. axis acceleration)
14 Drive Optimization with HMI Advanced
14.4 Frequency response measurements
Measurement time
Ramp time
t
t
14-439