CONTENTS ix 



PAGE 



94. Drum Winding. 



95. Multiple -drum Windings. 



96. Equalizer Rings. 



97. Series-drum Windings. 



98. Double Windings. 



99. Commutator. 



100. Brushes and Brush Holders. 



101. Field Windings. 



102. Direction of Rotation of Generators and Motors. 



103. Generation of Electromotive Force. 



104. Effect of Moving the Brushes. 



105. Saturation Curve. 



106. Magnetic Leakage. 



107. Determination of the No-load Saturation Curve of a Dynamo. 



108. Building up of E.m.f . in a Self-excited Generator. 



109. Distribution of Magnetic Flux. 



110. Commutation. 



111. Interpoles. 



112. Sparking. 



113. Voltage Characteristic or Regulation Curve. 



114. Regulation. 



115. Field Characteristic. 



116. Compound Generator 



117. Series Generator. 



118. Parallel Operation. 



119. Parallel Operation of Compound Generators. 



120. Tirrill Regulator. 



121. Electric Motors. 



122. Types of Motors. 



123. Speed Equation of a Motor. 



124. Methods of Varying Speed. 



125. Speed Characteristics of Motors. 



126. Torque Equation. 



127. Torque Characteristics of Motors. 



128. Starting of Motors. 



129. Applications of Motors. 



130. Power Losses in Dynamos. 



131. Efficiency. 



132. Limits of Output of Electric Machines. 



133. Storage Batteries. 



134. Applications. 



135. Boosters. 



CHAPTER V. 



SYNCHRONOUS MACHINERY, ALTERNATORS AND SYNCHRONOUS MOTORS . . 224 



136. Alternator. 



137. Types of Alternators. 



138. Electromotive Force Equation. 



139. Form Factor. 



140. Two-phase or Quarter-phase Alternator. 



141. Three-phase Alternator. 



142. E.m.f.'s, Currents and Power in Three-phase Circuits. 



143. Alternator Windings. 



144. Distribution Factors. 



145. Short-pitch Windings. 



146. Effects of Distributing the Winding. 



147. Multiple-circuit Windings. 



148. General E.m.f. Equation. 



149. Rating of Alternators. 



