Stepper motors offer innovative solutions in brushless motor technology and electronic controls for applications demanding precise, controlled movements. These integrated motors are an affordable, highly customizable option that benefits machine builders and OEMs with reduced engineering, installation, and start-up costs.
Stepper motors are driven by a series of electric pulses from a stepper drive. When the windings of a stator pole are energized by the drive, the pole exerts forces onto the rotor, causing it to turn. The resulting steps can be as small as a fraction of a degree. Because they move in discrete steps, they can be operated in an open loop, without feedback. The steps can be controlled with precision using open-loop, incremental or absolute encoders that can provide feedback to the user. Depending on the options the drive can help reduce cost, save energy and enhance performance all in one package. However, closed-loop products are also available and deliver enhanced performance, energy savings, and lower heat.
Stepper Motor Sizing
Proper sizing is most important for stepper motors. If the load is too large for the motor, the system can go into resonance, which can cause the rotor and the stator to lose synchronization and stall. This is most impactful in an open loop system that cannot correct itself. Steppers are different from other motors in that they produce excellent torque at low speeds, but at higher speeds, that torque starts to fall off quickly (more so in longer motor stack sizes).
Stepper Motor Torque
In other motors, like AC or DC motors, the torque is quite constant from low speeds up to some base speed like 1800 RPM or 3600 RPM. Above that speed, the torque will then start to fall off. Since they hold their torque to this higher RPM, they have much higher power because power is the product of both speed and torque.
Integrated Stepper Motors
Celera Motion offers integrated stepper motors through its subsidiary Novanta IMS, formerly Schneider Electric Motion. Novanta IMS has over 35 years of experience designing and manufacturing integrated stepper motor and micro-stepping drive solutions. Novanta IMS MDrive products integrate motor, driver, controller, internal encoder, and closed-loop performance, all in one compact package. Units are programmable and can be networked, satisfying the motion control requirements of many new and existing applications.
MDrive, the world-leading integrated motor brand, offers the broadest range of products and features, including MDrivePlus, MDrive Linear Actuators, and Liberty MDrive. Motor sizes range from NEMA 14 to 34, with standard and custom products available to meet the needs of new and existing applications. Communication options include RS-422/485 serial, CANopen, EtherNet/IP, Profinet, and ModbusTCP. Ingress protection ratings from IP20 to IP65 are available.
Stepper Motor Features
- Open loop, or closed loop with either an incremental or multi-turn absolute encoder
- Built-in protection circuitry
- IP65 rating with M12 connectors
- Input power range from +12 up to +70 VDC
- Auxiliary logic power supply input
- 20 microstep resolutions to 51,200 steps/rev
- Programmable motor run and hold currents
