Modern Polyphase Machinery (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1906 Excerpt: ...adopted by Ganz and Co., the Helios Co., and several other firms. See Figs. 79 and 81. The principal dimensions and electrical details are given below: --Table X. Output 1,500 kilowatts. Speed 83 revs. per minute. Periodicity 25 cycles per second. Number of field poles.... 36. Pole pitch 17.6 inches. Diameter of rotating f1eld Angular velocity of field Number of slots in armature. Number of slots per pole and phase Dimensions of slots in armature 16 feet. 4,380 feet per minute. 216. 2. 2.5 inches deep 1.5 inches wide. 3,850. 6,600. and Volts per phase Volts between terminals Amperes per phase 154 amperes at power-factor--.85. Length of air-gap 0.375 inch. Width of armature core Section of armature conductors Turns of wire per slot Current density in armature conductors 1,500 amperes per sq. in. Turns on each magnet pole Section of field winding.. Weight of revolving field Weight of complete machine Watts per revolution Output coefficient Efficiency full load 95i per cent. Efficiency half load 94 per cent. Rise of pressure between full and no load (non-inductive) Rise of pressure between full and no load with power factor zero 1.5 0.5 ins. copper strip. 221-tons. 6oh tons. lS,200. 35 5 J per cent. 22 per cent. The magnet cores are of cast steil bolted to the flywheels and the pole faces are laminated. The machinery of the Allgemeine Elektricitats Gesellschaft, Berlin (The Electrical Co., London), has been referred to in several places, particularly their method of constructing the armatures of their large alternators. Fig. 8.5 is an illustration of the armature frame of the 4,250 kilo-voltamperes (3.600 kilowatts on a power factor of.85) 6,500-volt alternators at Manchester F1g. 83.--4,000-Kw. 3-phase Generator Frame, As SUPPLIED TO THE MaNCHESTER CORPORaTIO..