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).
Letter to a recipient in France detailing a potential electrical fault with the dynamo polarity on S.S. chassis and the required fix.
| Identifier | ExFiles\Box 60\3\ Scan094 | |
| Date | 20th December 1928 | |
| X4040 Expl. Office. 20th December, 1928. EFC2/T20.12.28. Mr. G.W. Hancock, Hotel de France, Chateauroux, Indre, FRANCE. GWH{George W. Hancock - Head Chateauroux}: from EFC. Distribution Box incorporating Green Lamp Switch. Since your departure, we have discovered a feature of the electrical arrangement on these S.S. chassis which may cause you trouble. It is possible in some circumstances of switching, which you may in the ordinary course of events pass through, to cause the polarity of the dynamo to become reversed, and to cause as a result of this the fusion together of the cutout points. It does not necessarily follow that the cutout points will be fused together, because on first contact the battery current may correct the dynamo when the dynamo does start up with reversed polarity, and in that case you probably would not notice anything wrong unless you happened to be watching the cutout at the time. The object in writing this note is to tell you what to do if you do run up against this trouble. The only thing that can be done, but which will definitely cure it, is to remove the positive connection of the green lamp switch coil from the screw marked C. on the blueprint diagram herewith; from which screw you will note that the shunt coil of the cutout is also fed. This, of course, means that the green lamp will not work but as stated this is the only thing you can do out there to eliminate this unforeseen circumstance from the system. EFC. | ||