xii LIST OF ILLUSTRATIONS 



FIG. PAGE 



41. Connections of Energy Meter for Balanced Load 58 



42. Hot-wire Instrument 62 



43. Multicellular Voltmeter 64 



44. Multicellular Voltmeter 65 



45. Dial Pattern of Multicellular Voltmeter 65 



46. Ayrton-Mather Voltmeter 66 



47. Volt Balance 68 



48. Grau's Voltmeter . . . 69 



49. Westinghouse Voltmeter . . . . . . . . . .69 



50. Indicating Wattmeter .... 70 



51. Kelvin Astatic Wattmeter 70 



52. Drysdale Wattmeter 71 



53. Drysdale Wattmeter 71 



54. Power Factor Indicator 72 



55. Arrangement for recording Vibrations of Oscillograph .... 73 



56. Cam-plate of Synchronous Motor 75 



57. Magnet of Blondel Oscillograph 75 



58. Details of Blondel Oscillograph 76 



59. To illustrate Action of Continuous-current Armature when generating 



Single-phase Current .......... 79 



60. Slip-ring Connections for Two- and Three-phase Currents .... 80 



61. General Arrangement of Revolving Field Alternator 82 



62. Method of building up Armature Core ....... 83 



63. Method of supporting Armature Laminations . . . . . .83 



64. Ventilating Space-block 84 



65. Armature Core Construction 84 



66. Type of Construction for Narrow Armature ...... 85 



67. Yoke Construction ........... 85 



68. Field-pole Construction 85 



69 and 70. Methods of supporting Field-poles 86 



71. Types of Laminated Pole-shoes .86 



72. Showing Construction of Skewed Pole-shoe 86 



73. Field Construction for Turbo-generator 87 



74. Illustrating Two Types of Armature Winding 88 



75. Two-phase Armature Winding 89 



76. Three-phase Armature Winding 90 



77. Showing Armature Coils in Position 91 



78. To illustrate Effect of Pole-width on e.m.f 93 



79. To illustrate Armature Reaction in Alternators : (a) Current in Phase with 



e.m.f. ; (b) Current lagging by 90 ; (c) Current leading by 90 . 97 



80. To illustrate Principle of Walker Compounded Alternator ... 98 



81. Single-phase Transformer 103 



82. Berry Transformer 103 



83. Type of Transformer Construction 104 



84. Core of Three-phase Transformer 105 



85. Type of Three-phase Transformer 105 



86. Transformer Core Construction 105 



87. To illustrate Eddy-current Loss in Core 107 



88. To explain Difference between Calculated and Observed Core Loss . . 109 



89. Diagram of Auto-transformer 112 



