Planning, Installation And Service; Planning; Basicconsiderations; Selection Criteria For The Stepper Motor - Siemens SIMATIC S5 Manual

7

Planning, Installation and Service

Planning

7.1
7.1.1

BasicConsiderations

Which torque characteristic and which maximum torque are required?
Can a stepper motor achieve the required torque?
Will large fluctuations in load occur which can lead to loss of steps? (Load torque briefly
greater than motor torque.)
Will feedback (monitoring) of the actual axis position via additional position detectors be
necessary? (Possibly stepper motor with integrated position encoder.)
Is it advisable to use a drive unit which can detect and correct loss of steps?
7.1.2

Selection Criteria for the Stepper Motor

Mechanical dimensions and designs are not dealt with here.
What is the maximum torque?
Up to what pulse frequency can the motor achieve the required torque?
How high must the step number of the motor be to achieve the required position resolu-
tion?

Determining the MotorCharacteristics

7.1.3
Plant data
required positioning resolution
required traversing speed
maximum load torque of the shaft
k=
Planning
7-1