. Electric railway journal . rake notches currents are generated in the motors to producea retarding torque, the direction of the currents in the motorsbeing such as to strengthen the magnetism of the fields. If,however, the car is running backward and the controller handleis moved to the brake notches, the direction of currents gen-erated in the motors is such as to demagnetize the fields, so thatno braking effect is produced. To obtain braking when the car is running backward theBritish Thomson-Houston Company, Limited, of Rugby, Eng-land, has introduced controllers in which, when the contro
. Electric railway journal . rake notches currents are generated in the motors to producea retarding torque, the direction of the currents in the motorsbeing such as to strengthen the magnetism of the fields. If,however, the car is running backward and the controller handleis moved to the brake notches, the direction of currents gen-erated in the motors is such as to demagnetize the fields, so thatno braking effect is produced. To obtain braking when the car is running backward theBritish Thomson-Houston Company, Limited, of Rugby, Eng-land, has introduced controllers in which, when the controllerhandle is moved to the off position, connections are madewhich cause one or more of the motors to act as generators toproduce the desired effect. These connections are such that nobraking action is obtained during the forward running of thecar if the handle is in the off position. An arrangement pref-erable to this, however, is one in which the motion of the con-trol handle which produces braking for forward running will. Controller Arranged for Braking in Either Direction also produce braking for backward running. The B-49 control-ler shown in the illustration will give this result. The reverseswitch handle may be in either the forward or reverse posi-tion, when by moving the main control handle to the brakingnotches a rheostatic braking effect will be obtained for eitherthe forward or backward motion of the car. This controller issuitable for use with two 40-hp, 500-600-volt series motors andhas four series, four parallel and seven brake controlling important new feature of the B-49 controller is the June 3, 1911.] ELECTRIC RAILWAY JOURNAL. 983 mechanism by which a defective motor may be cut out of serv-ice without removing the cover of the controller. To cut out amotor it is only necessary to remove the reverse switch handlefrom its spindle and apply it to the cut-out spindle which pro-jects through the cap plate, shown in the illustration near theback edg
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