Using Motion Control; Maximum And Start/Stop Speeds - Siemens Simatic S7 Series System Manual

12.2

Using motion control

The motion control built into the CPU uses an Axis of Motion to control both the speed and
motion of a stepper motor or a servo motor.
Using the Axis of Motion requires expertise in the field of motion control. This chapter is not
meant to educate the novice in this subject. However, it provides fundamental information
that will help as you use the Motion wizard to configure the Axis of Motion for your
application.
12.2.1

Maximum and start/stop speeds

①
MAX_SPEED
②
SS_SPEED
● MAX_SPEED: Enter the value for the optimum operating speed of your application within
the torque capability of your motor. The torque required to drive the load is determined by
friction, inertia, and the acceleration/deceleration times.
● The Motion wizard calculates and displays the minimum speed that can be controlled by
the Axis of Motion based upon the MAX_SPEED that you specify.
● SS_SPEED: Enter a value within the capability of your motor to drive your load at low
speeds. If the SS_SPEED value is too low, the motor and load could vibrate or move in
short jumps at the beginning and end of travel. If the SS_SPEED value is too high, the
motor could lose pulses on start up, and the load could overdrive the motor when
attempting to stop.
S7-200 SMART
System Manual, 09/2015, A5E03822230-AC
Open loop motion control
12.2 Using motion control
The Motion wizard prompts you for the maximum
speed (MAX_SPEED) and Start/Stop Speed
(SS_SPEED) for your application.
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