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).
Comparison table of various dynamo models and their specifications.
| Identifier | ExFiles\Box 36\4\ scan 005 | |
| Date | 1st January 1919 | |
| -3- DYNAMO TABLES (CONTD) Machine. C.A.V. N.G.N.R. Lucas E.575 Lucas A.400 Bijur. Liberty. Smith T & M 3A. Smith T & M A.{Mr Adams} Smith T & M 2D. R.R. 20 HP. FIELD WINDING. rrgt. of coils. Two main coils in series. Two subsidiary coils in series. One main field coil. One control field coil on same pole. Four in series. Two main coils in series, one on each pole. Four in series. Two main coils in series, one on each pole. Four in series. Resistance of field winding(cold) 7.8ω (hot) 5.8ω (1) 8.7ω (2) 9.2ω 3.48ω ? 7.75ω 4.0ω 4.1ω Weight of copper composing winding (lbs.) Turns per coil. WEIGHT. Weight of machine complete (lbs). 36.5 29 39.5 30.5 13.5 25.25 32.0 31.75 R.R. 63. 20 TY/S.F. ME. C-G-19. 2458 | ||