THE DESIGN OF DIRECT-CURRENT 
101. 
_ 102. 
103. 
104, 
105. 
106. 
10%. 
108. 
109. 
110. 
DYNAMOS AND MOTORS. 
Upon what does the number of conductors depend which 
can be placed upon an armature of given diameter? 
Give the average winding height of a 6-inch smooth drum 
armature. 
What is the average height to which a 50-inch smooth 
ring armature is usually wound? , 
Give the average depth of slot of a 20-inch toothed arma- 
ture. 
Give a simple formula expressing the cross-section of the 
winding space on a smooth-core armature. 
What average percentage of the total winding space is 
occupied by insulation, etc., in an ordinary smooth-core 
armature machine? 
State formula giving the available inductor space on a 
smooth-core armature. 
Give formula for total number of conductors on a smooth- 
core armature, if the diameter of the core, the winding 
height, and the thickness of the wire are known. 
State the formula for the approximate total number of 
conductors on a toothed armature, if the armature 
diameter, the winding height, and the size of wire are 
given. 
What is the usual practice with reference to the number 
of commutator segments for dynamos of various vol- 
tages? 
