. Electrical world. of increased output, motors wereadded from time to time until practically all shafting in the oldbuildings was eliminated. In some of the later installations directconnected type motors were used in driving certain types of presses,such as the Huber. In these cases the motor was mounted on thepress shaft, the machine being bolted directly to the frame of thepress. In some of the later installations, field weakening besidesresistance in series with the armature, was introduced and found sat-isfactory. The question of reliability being an important factor in theoperation of t
. Electrical world. of increased output, motors wereadded from time to time until practically all shafting in the oldbuildings was eliminated. In some of the later installations directconnected type motors were used in driving certain types of presses,such as the Huber. In these cases the motor was mounted on thepress shaft, the machine being bolted directly to the frame of thepress. In some of the later installations, field weakening besidesresistance in series with the armature, was introduced and found sat-isfactory. The question of reliability being an important factor in theoperation of the Government Printing Office, instead of dependingon fuses to protect the motors in case of excessive overloads fromvarious causes, Mr. Tapley decided upon the wise plan of protectingeach motor with a circuit breaker. This, of course, added consid-erably to the expense of the motor outfits, but has been found inpractice to be an excellent investment. The electrical propositions presented in connection with the new. FIG- 33-—FIVE TWO-REVOLUTION PRESSES, MOTOR-DRIVEN. Government Printing Office were most intricate, and all credit is dueto Mr. Tapley in solving the various problems due chiefly to the tre-mendous proportion of current going into power apparatus. One ofthe most important was the continuance of the use of the existingvoltage or the installation of 250 volt dynamos. After some weeks ofcareful examination into the various details connected with thisproblem, it was decided to adopt 125 volts for the new equipmentstation. The new Office is as stated above the most complete andunique plant of its character in this or foreign countries. Thebuilding alone contains over 600 motors in sizes from 1-6 to 100 horse-power and over 500 of the motors are of Crocker-Wheeler manufac-ture. In the new equipment many novel methods of application havebeen evolved, this being particularly so in the electrotype foundry, inwhich department every machine is individually driven as in the o
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectelectri, bookyear1883
