Design and Application of a Solid-State AC Motor Starter

This paper will explore the design, application, and field operating experience of the first complete line of 25-1000 hp solid-state ac motor starters. The contents are as follows: 1) the basic requirements of ac motor starting; 2) power circuitry-a brief review of solid-state; 3) a complete solid-state ac motor starter with provision for reduced voltage starting; 4) application problems, advantages and disadvantages of solid-state; 5) the ``hybrid'' motor starter; 6) new dimensions for squirrel-cage motors using solid-state control; 7) limited range speed control using variable voltage, fixed frequency; 8) the universal replacement. Is it practical?