THE DESIGN OF ALTERNATING 
GENERATORS AND SYNCHRONOUS 
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MOTORS. 
What is understood by the term ‘‘voltage drop’’ in an 
alternator and what machine characteristics are used in 
its investigation ? 
What is understood by the ‘‘open circuit characteristic’’? 
Give the formula stating the relation between the field ampere 
turns and the useful armature flux. 
Plot the no-load characteristic and the apparent resistance 
curve for an open circuit test of the following data: 
Excitation in ampere turns Armature pressure 
1,000 ampere turns 820 volts 
2,000 ay 1,620 ‘‘ 
3,000 ie 2,340 ‘ 
4,000 ‘$ 2,960. * 
5,000 * 3,380 
6,000 3,600 ‘* 
What is understood by the ‘‘short cireuit characteristic’’ ? 
How is the short cireuit characteristic of an alternator de- 
termined experimentally ? 
Give the equation of the short circuit characteristic. 
What is the load characteristic of an alternator ? 
