Hawkins Electrical Guide v. 06 (of 10) / Questions, Answers, & Illustrations, A progressive course of study for engineers, electricians, students and those desiring to acquire a working knowledge of electricity and its applications

by N. Hawkins

Ques. What name may appropriately be applied to the motor?

Ans. It may be called the repulsion induction motor, because it is constructed for repulsion start and induction running.

Ques. Describe a compensated repulsion motor.

Ans. In its simplest form it consists of a simple repulsion motor in which there are two independent sets of brushes, one set being short circuited, while the other set is in series with the field magnet winding, as in the series alternating current motor.

Ques. What names are given to the two sets of brushes on a compensated repulsion motor?

Ans. The energy or main short circuiting brushes, and the compensating brushes.

Fig. 1,912.—Diagram of connections of Sprague reversing type of single phase compensated repulsion motor. As shown, there is a special reverse field winding having terminals for connection to a four pole double throw switch.

Ques. What is the behavior of the armature of a compensated repulsion motor at starting?

Ans. It possesses at starting most of the apparent reactance of the motor, and the effect of speed is to decrease such apparent reactance, the latter becoming zero at either positive or negative synchronism, and negative at higher speeds in either direction.