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).
Recommendation to modify the inspection lamp plug socket with different diameter pins to prevent incorrect connection for external charging.
| Identifier | ExFiles\Box 40\2\ Scan009 | |
| Date | 9th February 1920 | |
| R.R. 235 a (100 T) (R.F. 846 6-8-19) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2460. X.3552 Extract from CK{Mr Clark}5/T9.2.20. X.3552. Inspection Lamp Plug Socket. We are recommending in our Instruction Book, that, under certain circumstances, charging from an external source be resorted to. For this purpose we wish to make use of the inspection lamp plug socket and and inspectionlamp plug. But in order that there shall be no possibility of connecting up the charging source in the wrong direction, we think that the two two pins and sockets should be of different diameters. Would you, therefore, kindly let us know if such a modification in the boxes supplied to us would be agreeable to you. In the meanwhile, also, until this matter is decided, we should probably like you to arrange to mark the necessary + and - to these sockets on the switchbox cover. After receiving your remarks on this matter, we will then place it in the hands of our Production Dept. to carry through if we so desire, and you agree. | ||