Glossary · Motion control and drives
Step angle
Also known as: Full-step angle
German: Schrittwinkel
In stepper motor technology, the step angle is the rotation of the motor shaft per full step, determined by the motor's construction; typical hybrid stepper motors have 1.8° (200 steps per revolution) or 0.9° (400 steps per revolution).
- Motion control
In one sentence
The step angle is the shaft rotation per full step, set by the motor design, typically 1.8° (200 steps/rev) or 0.9° (400 steps/rev).
Example
The datasheet of a NEMA 17 stepper motor for a label printer's feed roller gives a step angle of 1.8° ± 5 % per full step.
How it applies
- Engineering: The step angle and the mechanics (gear, lead screw, belt) define the travel per full step. Microstepping divides this further, for example 1.8° / 256 ≈ 0.007°.
- Commissioning: Scaling parameters (steps per millimeter, steps per revolution) are derived from the step angle and the microstep setting; both must match the installed motor.
- Operation: Datasheets state a step angle tolerance (often ± 3 % or ± 5 % of a step, non-cumulative). It limits the positioning accuracy in open loop regardless of the microstep resolution.
- Documentation: Give the step angle together with its tolerance and don't derive a positioning accuracy from the step angle alone. Resolution and Accuracy are different quantities.