2-Phase and 5-Phase Step Motor Comparison

Resolution

Structurally, the 5-phase motor is not that different from the 2-phase motor. The rotor in both motors has 50 teeth. The difference is that because the 5-phase motor has 10 poles, 2 per phase, the rotor only has to move 1/10 of a tooth pitch to line up with the next phase. In the 2-phase motor, the rotor has to move 1/4 of a tooth pitch to line up with the next phase (8 poles, 4 per phase).

This results in the 2-phase having 200 steps per rotation, 1.8° per step, while the 5-phase has 500 steps per rotation, 0.72° per step. The increased resolution of the 5-phase is inherent to its design. When coupled with a microstepping driver, the 5-phase motor can make steps as small as 0.00288°, however, position accuracy and repeatability are still subject to the motor's mechanical accuracy. The mechanical accuracy of both the 2-phase and 5-phase motor is ± 3 arc minutes (0.05°).