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 Figure 3 ) The center pair of wheels of each truck was not powered A gearcase, which enclosed the gears, carried the grease for their lubrication Grease could be added, as needed. by means of a filler cap in the gearcase.

1 Powerplant

The unit was provided with two 12-cylinder diesel engines, each coupled directly to an electrical unit containing a 600-volt generator which provided power for the traction motors and an alternator which provided power for cooling and ventilating fans Hereinafter, this electrical unit will be referred to as the generator Each diesel engine and generator were mounted longitudinally in the engineroorn with the generator of each engine positioned toward the end of the unit. The generator end is considered the rear of the engine The forward engine and generator, referred to as No 1, provided power for the two traction motors mounted on the front truck, while the rear engine and generator, referred to as No 2, provided power for the two traction motors mounted on the rear truck.

Electrical controls which governed the operation of the power or primary circuit of each engine and generator were contained in a cabinet mounted on the end walls of the engine room toward the rear of each engine. A power operated reverser switch, remotely controlled, was used to change the direction of the flow of electrical current to the traction motors for forward and reverse movements of the loco- motive unit The reverser had three positions: forward, backward, and neutral The reverser could be locked in the neutral position by placing a pin through a hole in the hub of the switch which aligned with a hole in the frame. Although power to the two traction motors in that circuit was cut off when the rover ser was placed in the neutral position, the diesel engine and generator would respond to their controls

In addition to the main generator, a 10-kw auxiliary generator, driven directly by each of the diesel engines, provided direct current at approximately 74 volts for lighting, control circuits, generator field excitation, fuel pumps, and charging of the batteries. This auxiliary generator was mounted above the main genera- tor.

The armature of the traction motor was carried at each end by sealed, grease-lubricated roller bearings The pinion gear is mounted on the end of the armature opposite the com- mutator end. The amount of lateral movement of the armature was controlled by the commutator-end hearing with an end plate secured to the end of the armature which bore against the H-ring of the roller-bearing assembly The end plate was secured to the end of the armature shaft by a threaded projection screwed into a threaded cavity in the center of the armature end. Two locking screws which bore against the end of the armature shaft prevented the end plate from turning. Each bearing as- sembly was provided with oil throwers and seals to retain the lubricant

2. Locomotive Controls

The controls for operating the lead unit and other units when they were coupled as a multiple-unit locomotive were located in the control compartment in the vicinity of the engineer's position. Included as part of the controls were the throttle, which controlled the speed of the diesel engine; a transition lever, which determined the power or dynamic braking aspect; a reverse lever, which determined direction; and two airbrake valves. The reverse lever was electrically connected to and con- trolled the position of the power reverser switches, previously described in addition, a number of switches, gauges, and warning lights or indicators were provided. The dial of a speed recorder indicated the speed of the locomotive, however, tapes were not used to record the speed. A load meter indicated in amperes (from 0 to 1,500), the amount of current supplied to the traction motors in No 1 circuit. Airbrake gauges were also provided (See Figure 4 )