xii LIST OF ILLUSTRATIONS 



no. 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 



