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).
The performance of a modified 56 coil dynamo (OS.95.SS) for the Phantom II, fitted to the Prince of Wales' car.
| Identifier | ExFiles\Box 60\1\ Scan210 | |
| Date | 25th February 1930 | |
| X.7660 7660 X.5664D. PHANTOM II. 56 COIL DYNAMO OS.95.SS.{S. Smith} WITH POLAR MODIFICATION. The polar modification to this otherwise standard Phantom II machine on the Prince of Wales' car 115-WJ. was put in hand to D.O. instructions when it was thought that there would not be time to produce a proper higher output machine to our instruction EFC3/AD28.1.30. It was thought that there might be a sufficiently increased output by so modifying the standard machine to meet the case. The machine, modified and designated OS.95.SS.{S. Smith} - M.H.O. was received by us and bench tested in the laboratory when it was found that, though the curve had been appreciably raised at high speeds, the output on the peak was unaffected. This was considered insufficient. As regards heating, the machine was quite O.K. the figures being :- Output. 13.2 amperes at 1620 r.p.m. Temperature. 17 - 57 - 74. B = 13º C = 122º (Angles of standard machine 9º 122º). On the results obtained above it was considered that this machine would not be suitable for the purpose, and in our EFC4/AD10.2.30 we pressed for the provision of the higher output machine referred to in PD.45. which was duly produced and which, as will be seen by reference to that report gave, after slight modification, a performance which was considered suitable for the purpose. EFC. | ||