The model number of a stepper motor consists of four segments, representing frame size, motor type (BYG stands for hybrid type, BC for variable-reluctance type), phase number, and rotor tooth quantity respectively.

1. Frame Size

Also known as motor outer diameter. Standard specifications include 28, 42, 57, 86, 110 and 130.

2. Motor Type

Variable-Reluctance Stepper MotorThe stator is equipped with windings, and the rotor is made of soft magnetic materials. It features a simple structure and low cost with a small step angle down to 1.2°. However, it suffers from poor dynamic performance, low efficiency, severe heat generation, and insufficient reliability.

Permanent Magnet Stepper MotorThe rotor of a permanent magnet stepper motor is made of permanent magnetic materials, and the number of rotor poles equals that of stator poles. It delivers favorable dynamic performance and high output torque, yet has low accuracy and a large step angle (typically 7.5° or 15°).

Hybrid Stepper MotorHybrid stepper motors combine the advantages of variable-reluctance and permanent magnet types. The stator carries multi-phase windings, while the rotor adopts permanent magnet materials. Numerous fine teeth are fabricated on both stator and rotor to improve step accuracy. Such motors provide high output torque, excellent dynamic performance and small step angles, but come with a complicated structure and relatively higher cost.

3. Phase Number

It refers to the number of excitation coil pairs that generate alternating N and S magnetic poles, generally denoted by the symbol m.

Changzhou Hetai Motor & Electric Appliance Co., Ltd. mainly manufactures hybrid stepper motors and drivers. Feel free to contact us for inquiries.