Abridgment of progress in the design of the single-phase series motor

The paper deals with the development of the design of the single-phase series motor and some of the main features in both electrical and mechanical proportions which determine the service capacity in the application of this type of motor to railway electrification. Intensive study and development begun in the early part of 1927 resulted in the production of a single-phase series motor with more than enough capacity to meet the present day requirements of the American railroads. A brief description is given of this motor and of some of the novel features which made this recent progress possible. Since this motor was developed, built, and tested, further possibilities of increasing rating or decreasing the size and weight for the same rating have been found and will result in further progress in the design of the single-phase series motor.