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 winding details for the S.S. Chassis Starter Motor Gear No. 2 Scheme.
| Identifier | ExFiles\Box 64\4\ scan0074 | |
| Date | 18th July 1928 | |
| To BY/RD. from EFC. X765513 EFC1/T18.7.28. S.S. CHASSIS STARTER MOTOR GEAR NO.2 SCHEME. Answering your BY/RDs/ML17.7.27 we have now considered the matter of the windings and specify these as follows :- For the winding of the switch operating the main heavy current contacts, wire of 22 S.W.G. D.C.C. should be used. For the winding of the auxiliary relay switch which breaks the teazer circuit and makes the hold-on circuit, we specify wire of 26 S.W.G. D.C.C. In regard to the non-inductive resistance which is placed in parallel with the main switch winding, the previous specification of Glowray wire which we gave you will be, so far as we can see previous to test, quite suitable. E.F.C/T 5.7.26 It will be observed that both the frames of the relay switch and main switch respectively must be insulated from one another and from earth. There is a mechanical interlock through the two and on our own inspection of LeC.2572 we do not see the provision for such insulation. Perhaps you can yourself see how this is provided for. (Handwritten insertion: 'between' above 'through the') EFC. | ||