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 colour-coding scheme for low tension conductors on the 40/50 HP Chassis.
| Identifier | Morton\M11\ img239 | |
| Date | 1st October 1919 | |
| To EFC. from E.{Mr Elliott - Chief Engineer} Copy to CJ. " " BN.{W.O. Bentley / Mr Barrington} " " OY. " " DA.{Bernard Day - Chassis Design} " " EH. R - GENESIS OF AL. & LT WIRING CONDUITS ORIGINAL on 40/50 E3/G1/10/19. Extract x.2448 x.3659 RE LOW TENSION CONDUCTORS. 40/50 H.P.CHASSIS. In connection with the above matter, would you kindly note that Mr. Royce thinks we should have a number of low tension conductors of the following colours :- red, blue, black, white, yellow, and green, and that we should use these colours as judiciously as possible so that they will serve the purpose of identifying each conductor end with its proper terminal. It is considered impossible to have a different colour for every conductor, and we must therefore adopt a scheme in which we have a limited number of colours, using the same colours two or three times over, but in such a manner that other features of the wiring system will serve the purpose of completing identification of the conductor ends and their terminals. For example, the conductors flowing away from the bottom edge of the distribution board should divide and go to right and left of the dashboard. We may therefore have similar colours in the right and left hand groups of conductors. Would you therefore please proceed to order up conductors of the braided type which you sent to us. It is considered that 70/36's should be used for all of the conductors flowing away from the top edge of the distribution board, and that the same size of conductors should be used for the remainder, with the exception of conductors having small currents of two or three amps. which should be in 64/38's. (Contd.) H'W 3327 (200 M) (R'D 408 S0-4-14) B'W STREET | ||