The development of motor control-gear

The paper is a review, in general terms, of present-day practice in the design of industrial motor control-gear. Its scope is limited to what may be described as standard industrial equipment, and the subject is approached from the standpoint of the user of such equipment. In the first part of the paper the principles on which modern design has been established are reviewed, and in the later Sections some of the factors that are likely to affect the future development are discussed. The author states the case for the utmost simplicity in design and for greater latitude in the value of starting-current peaks that may be allowed. Possible development in contact materials is discussed, and reference is made to the possibility of achieving some measure of standardization.