CIRCUIT ARRANGEMENT FOR A DC MOTOR OF A TRAINING VEHICLE CONNECTED IN A SERIES WITH A STEP-BY-STEP ADJUSTABLE DRIVING OR BRAKING RESISTOR

摘要

The arrangement is for a drive motor connected in series with a step-wise variable running or braking resistance and in which a motor winding with zero diode is fed from a separate source via adjusting means, whilst means are provided to receive a signal from a current transformer which signal is determined by the variation with time of the armature current occurring when the run or brake resistance is varied. The output of the differential element is connected with the control of the adjusting means via an electronic circuit which only responds when its input signal reaches a pre-determined value and supplies a signal of given duration to the control independent of the variation with time of the input signal.