2 Phase and 3 Phase Motors

MOONS' offers a variety of hybrid step motors with varying phases and steps. Depending on the application, each has its own set of advantages.

• 2 Phase - 1.8-degree step angle

This is the most popular step motor. It combines torque, speed, and accuracy well. 2 phase motor drives are very common and economical because of their high volume. A motor is controlled by applying full current to its windings as the drive makes one full step. This causes the motor to move in full step increments. A motor that is stepped at different rates can make a distinctive sound and vibrate (resonate) at certain speeds. This is not a problem for most applications. If it is an issue, motors can be controlled with micro-stepping drives that smooth motor torque. A drive can be programmed to avoid resonance speeds in many cases. MOONS' offer two-phase 0.9-degree step motors and three-phase 1.2-degree step motors for applications that require even higher accuracy or smooth, quiet motion.

• 2 Phase - 0.9-degree step angle

As each step moves only ½ times as far as 1.8-degree motors, these motors are very accurate and smooth. This motor is driven exactly like the 2-phase, 1.8-degree motors. For the same speed, these motors must have a step rate that is 2 times that of a 1.8-degree motor. This higher step rate leads to less torque at high speeds. For many applications, high speed is not necessary, or higher voltage drives can increase torque at high speeds. An example of a good application for 0.9-degree motors is security cameras. By using these motors, the camera can be precisely moved without "camera shake" which causes the picture to vibrate. MOONS' offers small encapsulated sizes that reduce camera package size, and helps withstand the outdoor environment.

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• 3 Phase - 1.2-degree step angle

The use of three phases inherently helps to reduce torque ripple and smooth motor performance. 3 phase motors require a 3-phase drive that is different than the drive for 2-phase motors. As compared to the 1.8-degree two-phase motors, the low-speed torque is somewhat less. However, MOONS' improvements to their design minimize this difference. High-speed torque can also be comparable. Furthermore, MOONS' size 24 three-phase motors feature PowerPlus technology for maximum torque. In applications requiring maximum performance and smooth, precise movement, three-phase motors are often used. An example of a good application for three-phase motors is in performance lighting. To avoid disturbing the performance, these spotlight lights need to move quickly and operate quietly.