ALTERNATING GENERATORS AND SYNCHRONOUS MOTORS. 13 
The temperature rise should not exceed 75 degrees Fahren- 
heit on any part of the motor, and the full load efficiency 
with a power factor cos gy =0.9 should not be less than 
94%. 
451. Input.—tThe electrical equivalent of the mechanical output 
is equal to 550 .746=410 K.W. With an efficiency of. 
ga) $4" the Glesicical input will be wag 435 KVA. with 
fact SV pe igs VA 
a power factor, cos p= 1; and— 97-5 = 
with a power factor, cos p = 0.9. 
452. Phase Current.—From Equation (5) the armature 
a 485,000 
1.73 X 3,460 
435,000 
1.73 x 3,460 
.) * phase current is equal to =81 amperes, with 
cos p=0.9, and 
=72.5 amperes with 
cos p = 1. 
453. Total Flux.—The total amount of useful magnetic flux 
KVA. 485 
eS = 1.29 
3 Ni 1 87S 
and Fig. 62, where 2p x /, =67.5 10°. Or, as the number 
120 x 50 
| | 375 
the useful flux per pole will be about 
will be found by means of the ratio, 
of poles is equal to 2p = = 16, see Equation (7), 
O7-5X10 4 955108 
16 
lines. 
454. Armature Winding.—The armature winding will be of 
the former wound long coil type, placed in open slots. As- 
suming a total number of slots S= 96, that is, 2 per pole and 
phase, with a pole arc ratio of 0.65, found by means of 
Table 14, the form factor will be found equal to 2.3. 
455. Armature Conductors.—By the application of the 
Equation (35), the number of armature ampere conductors 
485 2.3 
os ‘spales! |: SRE oes deve TS 
is equal to a75 (84 X C.,) X 67.5 X 10 20x 1017? where 
