A-C Multiple-Unit Car Control Equipment

Recent years have witnessed a growing demand for improvements in a-c multiple-unit car equipments. This paper, together with three companion papers,^1,2,3 deals with principal objectives of the improvement program and shows how they were attained in new equipments now going into revenue service on a large eastern railroad. The principal improvements center in the use of four newly designed traction motors per car, instead of the usual two, and a resistance acceleration scheme containing a new motor-driven cam controller. Improvements also were made in protective schemes and in arrangement of apparatus. Dynamic braking, now being worked out as a next logical development step for a-c cars, also is discussed briefly.