ALTERNATING GENERATORS AND SYNCHRONOUS MOTORS. 7 
conductor section of the field coils and choose the most sui- 
table size of S. W.G. 
308. Allowing for the maximum excitation a current density of 1600 
amperes per square inch, calculate the maximum neces- 
sary excitation current and the number of turns per pole. 
309. State the most suitable arrangement of the turns and make a 
sketch 4 full size of two adjacent pole pieces showing their 
respective windings. for this purpose assume that in the 
radial direction the total room taken up ies the bobbin and 
end plates is about 1 inch. 
310. Calculate the excitation loss corresponding to the full cos Pp 
= .9 load. 
311. Calculate the warm armature resistance and determine the 
armature copper loss at full load. 
312. Calculate the weight of the teeth and the iron losses in same. 
313. Calculate the weight of the armature core and the iron losses 
in same. 
314. By means of Equation 43 and Fig. 25 of the Instruction Book, 
calculate the efficiency, at full load, of this synchronous 
motor. 
315. By means of Equation 41 of the Instruction Book, calculate 
the temperature rise on the field coils. 
316. By means of Equation 40 of the Instruction Book, calculate 
the temperature rise on the armature. 
317. By means of Equation 39 of the Instruction Book, calculate 
the output coefficient of this synchronous motor. 
318. Collect in tubular form the different data of this synchronous 
motor. 
Printed in U. 8. A. 
