24 ALTERNATING GENERATORS AND SYNCHRONOUS MOTORS. 
482. Total Losses.—The various losses in the fully loaded 
motor carrying a leading current with a power factor of 
cos pg = 0.9, consist of the excitation energy of 4,680 
watts, armature copper loss of 6,400 watts, iron losses of 
9,740 watts and an assumed value for friction and venti- 
lation losses of 6,500 watts. 
483. Full Load Efficiency.—From the above the full 
load efficiency, see Equation (48), is found equal to 
walt =94%, which is in ac 
410000+-4680-+-6400-+-9740+-6500 °° “°’ ms 
cordance with the specification, Par. 446. 
484. Summary of Design.—The design of this motor is very 
economical, as indicated by the output constant which 
63? x 12 x.375 
485 
from Equation (39), is.equal to f= 
= 37 x 10%. 
The weights of the various parts are: Armature iron stamp- 
ings, 850+4,500=5,350 lbs.; armature copper 630 lbs., 
and the field copper 760 lbs. The above weights when 
compared with the data in Fig. 14, indicate an economical 
utilization of the material, 
Printed in U. 8. A, 
