miniature motors are built with more costly but higher strength magnets. Also, for reduced susceptibility to electrical noise, some are designed with relatively low inductance. Manufacturers often indicate
motor size with a Size designation of the diameter in 1/10s of an inch. Thus, a Size 30
motor has an outside diameter of 3 in. For feedback, manufacturers offer a range of
miniature optical and magnetic encoders,
ac and dc tachometers, and resolvers. Some companies supply line-driver encoders...
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