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 S. Smith & Sons requesting a switchbox modification for a polarised socket for an inspection lamp and battery charging.
| Identifier | ExFiles\Box 40\2\ Scan021 | |
| Date | 6th August 1920 | |
| X.3552. EFC4/T. c. Ds. c. Ls. 6th August, 1920. Messrs. S. Smith & Sons, Ltd., 179-185, Great Portland St.{Capt. P. R. Strong}, London, W.1. Dear Sirs, X.4164 X.3552. Re Switchbox. Further to our EFC2/AT of 4th inst., we omitted in the letter and diagram of connections of switchbox sent with it to mention that we should also require in the switchbox an inspection lamp plug. Will you, therefore, in getting out this switchbox, kindly make provision for such a socket together with a suitable plug for use with it. We should like the plug to be made with pins of different diameters so that this can only be put in one way round. Further, we should like to have the socket marked + and - to indicate the correct polarity. The reason we require this is that we recommend in our Instruction Book using such a connection for the purpose of charging a battery in position on the car when in the garage. Yours faithfully, | ||