. Railway mechanical engineer . ntrol magnet,a relay known as a transition relay and a spring. Thisis accomplished by an interesting mechanical movementA brief summary of the sequence of operations of thisstater is as follows: First.—The operating magnet isexcited, closing the armature, compressing a spring and con-necting the motor to the source of supply through the trans-former. Second.—After the motor has attained a suitablespeed, the transition relay operates a latch, permitting thecompression spring to disconnect the motor from the trans-former and the transformer from the line, and to c
. Railway mechanical engineer . ntrol magnet,a relay known as a transition relay and a spring. Thisis accomplished by an interesting mechanical movementA brief summary of the sequence of operations of thisstater is as follows: First.—The operating magnet isexcited, closing the armature, compressing a spring and con-necting the motor to the source of supply through the trans-former. Second.—After the motor has attained a suitablespeed, the transition relay operates a latch, permitting thecompression spring to disconnect the motor from the trans-former and the transformer from the line, and to connect themotor to the line. Third.—When the operating magnet isde-energized, the armature falls open and the motor is dis-connected from the supply lines. Any point on the movablecontact completely bounds an enclosed area each time thecompensator goes through one cycle of operation, passingprogressively from off to start, to run, and finallyagain to the off position. The compensator is submerged in oil with the exception. E. C. & M. Automatic Compensator for Alternating Current Motors of the terminal board used for connecting the transformervoltage taps. The oil accomplishes several purposes; itcools and insulates all parts carrying current, it providesconstant and liberal lubrication for the moving parts and itquickly quenches the arc which is formed when the contactsare separated. A special oil is used which has a high flashpoint, but which is still liquid enough at zero degrees, F.,to allow free operation. On account of a large volume ofoil and the freedom with which copper particles and carboncan settle harmlessly at the bottom it is not necessary tochange the oil for at least five years of average service. The arrangement of taps to the transformer coils is suchthat by means of the flexil)le leads it is possible to easilyadjust the voltage for starting, that is, if the motor fails tostart promptly under normal load conditions with the leadson certain taps, they may
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectrailroadengineering
