Siemens SIMATIC FM 453, Руководство пользователя

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9-72
FM 453 Servo Drive / Step Drive Positioning Module
C79000-G7076-C453-01
Simple characteristic
The machine data for acceleration (MD40) and deceleration (MD41) can be
used to adapt the transition response of the command variable defined by the
interpolator to the transition response of the controlled system.
v
a
t
t
MD41
MD40
t – time
v – speed
a – acceleration
MD Designation Value/Meaning Unit
40 Acceleration 0 = without ramp
1 100 000
[10
3
MSR/s
2
]
41 Deceleration
1...100,000
[10
3
MSR/s
2
]
61 Control mode 0 = Servomotor with servo position
control
1 = Stepper motor with servo posi-
tion control
7 = Stepper motor without servo
position control
MSR stands for measurement system grid (see Section 5.3.1)
Stepped characteristic
The stepped characteristic is specially designed to comply with the demands
of stepper motors on the frequency/time function which result from the fall
off in torque with increasing stepper motor speed. A discontinuous traversing
movement with a programmed speed is initiated or stopped below the Start/
Stop frequency.
For higher traversing velocities, a ramp-shaped control cycle, which builds
on the Start/Stop frequency, takes place within two velocity ranges with ac-
celeration values of different parameterization capability.
When phases of constant travel are reached, or axis standstill, a minimum
holding time is inserted for these states to esure that the motor or axis vibra-
tions subside before a new acceleration phase is implemented.
Description of Functions