From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Data table and schematic diagram for a tapped winding, detailing turn counts and corresponding voltages.
| Identifier | ExFiles\Box 32\4\ Scan055 | |
| Date | 29th September 1924 guessed | |
| -2- Condition NO. | Position of tappings (Expressed in No. of turns) | Total No. of turns | Equivalent nominal voltage. --- | --- | --- | --- 78. | 10,20,40,90,15,15,15,45. | 265 | 212 79. | 5,10,20,40,90,15,15,15,45. | 270 | 215.6 80. | 2,5,10,20,40,90,15,15,15,45. | 272 | 217.6 81. | 1,2,5,10,20,40,90,15,15,15,45. | 273 | 218.4 82. | 2,1,2,5,10,20,40,90,15,15,15,45. | 275 | 220 83. | 10,20,40,90,15,15,15,45,15. | 280 | 224 84. | 5,10,20,40,90,15,15,15,45,15. | 285 | 228 85. | 2,5,10,20,40,90,15,15,15,45,15. | 287 | 229.6 86. | 1,2,5,10,20,40,90,15,15,15,45,15. | 288 | 230.4 87. | 2,1,2,5,10,20,40,90,15,15,15,15,45,15. | 290 | 232 Diagram Details: E Winding Sections (turns): 90, 15, 15, 15, 15, 45, 15, 45 Tap Voltages: 72V, 84V, 96V, 108V, 120V, 156V, 168V, 200V TOTAL 255 turns 13 - 14 SWG. D.C.C. | ||