Standard AC Motors
Low-Speed Synchronous Motors

SMK Series

Low-speed synchronous motors are continuous rated synchronous motors in which quick bi-directional rotation is possible. The basic construction of low-speed synchronous motors is the same as that of stepping motors. Since they can be easily driven by an AC power supply, they are sometimes called AC stepping motors.

Low-Speed, Synchronized Rotation

The motor rotates at a speed proportional to and accurately synchronized with the power supply frequency.
A fluctuation in load does not affect the rotation speed.
At 50 Hz 60 r/min (30 r/min)✽
At 60 Hz 72 r/min (36 r/min)✽
✽ ( ) indicates SMK014MA-□.

Continuous Rated Capacitor Run Motor

This capacitor run motor can be easily driven by a capacitor only (An external resistor is needed for SMK5□.) This motor can be driven at a continuous rating even when bi-directional operation is required.

Superb Starting, Stopping and Reversing Characteristics

If operated within the motor's permissible load inertia, the motor can start, stop and reverse within 1.5 cycles (0.03 seconds at 50 Hz, 0.025 seconds at 60 Hz) of power supply frequency.

Suitable for Equipment that Starts and Stops Repeatedly Such as Conveyors

Bi-Directional Operation Can be Repeated Continuously

Precise Positioning

The motor can be stopped instantly by turning off the power supply. The stopping accuracy within the motor's permissible load inertia is ±10˚.

Vertical Operation is Possible

The motor rotates at a constant speed even during gravitational operations. Low-speed synchronous motors are suitable for applications, such as an elevator mechanism, in which vertical operation at a constant speed is required.

Load Holding is Possible

Since its structure is the same as that of a stepping motor and a permanent magnet is used in the rotor, the low-speed synchronous motor has holding torque even when the motor is not energized. When used with a gearhead, comparatively high holding torque can be utilized.
● When a DC power supply is used, holding torque almost equal to that of a stepping motor can be produced.

Double-Shaft Type

This type is useful for installing a clean damper for vibration absorption or a slit plate for home detection.