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THE THOUGHT IS IN THE QUESTION THE INFORMATION IS IN THE ANSWER
A PROGRESSIVE COURSE OF STUDY FOR ENGINEERS, ELECTRICIANS, STUDENTS AND THOSE DESIRING TO ACQUIRE A WORKING KNOWLEDGE OF
A PRACTICAL TREATISE by HAWKINS AND STAFF
[Illustration: THEO. AUDEL & CO. 72 FIFTH AVE. NEW YORK.]
COPYRIGHTED, 1915, BY THEO. AUDEL & CO., NEW YORK.
~ALTERNATING CURRENT SYSTEMS~ 1,531 to 1,586
Advantages of the alternating current--~classification of systems~--vector summation; examples--~forms of circuit~: series, parallel, parallel series, series parallel--~transformer systems~: individual transformers; transformation at distribution centers--~single phase system~; two wire transmission and three wire distribution; objections to single phase systems; advantages--~monocyclic system~--~two phase systems~: adaptation; ordinary voltages used; two phase three wire system; two phase five wire system--~three phase systems~: six wire; four wire; three wire; connections: star, delta, star delta, delta star; evolution of three wire system; pressure and current relations; connection of transformers; open delta connection--~change of frequency~--Schaghticoke-Schenectady transmission line--~transformation of phases~: three to one, three to two, two to six, and three to six phase--~Scott connection~ for transforming from three to two phase--three to two phase with three star connected transformers--~economy of a.c. systems~--~relative weights of copper required for polyphase systems~--aermotor towers of Southern Power Co.--~choice of voltage~--~usual transmission voltages~--~diagram of three phase distribution~--~mixed current systems~; usual d.c. pressure on traction lines; use of mixed systems.
~Classification of auxiliary devices~: switching devices, types--current or pressure limiting devices, types--lightning protection devices, types--regulating devices, types--synchronous condensers, types--indicating devices.
Definition of a switch--behaviour of the current when the circuit is broken--points on design--installation of single throw and double throw switches--plug switches--~forms of break~: open, enclosed, fuse, horn, oil--disconnecting switches--pole top switches--~horn break switches~--motor starting switch--~oil switches~; nature of an oil break--~remote control oil switches~--~motor operated switches~--rupturing capacity of oil switches--~float switches~.