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).
Earthed wiring scheme for chassis 6 EX, including dynamo, battery, and starter motor connections.
| Identifier | WestWitteringFiles\E\September1920\ Scan31 | |
| Date | 3rd September 1920 | |
| To R.{Sir Henry Royce} from EFC. c. to CJ. c. to E.{Mr Elliott - Chief Engineer} x.to Hs.{Lord Ernest Hives - Chair} c. to Da.{Bernard Day - Chassis Design} c. to By.{R.W. Bailey - Chief Engineer} c. to EP.{G. Eric Platford - Chief Quality Engineer} ORIGINAL (stamp) EFC2/T3.9.20. I-q (handwritten) 8 (handwritten) X. 3659 - EARTHED WIRING SCHEME. X 39236 (handwritten) Reference your note R4/G24.8.20, re chassis 6 EX, my impression is now that you would like all dynamo and battery connections brought up to the board and a common earthing of the negatives of the battery and dynamo made through a fuse on the board. This will avoid the circuit of the dynamo to the battery including the earthing fuse, which circumstance I think you have agreed is undesirable. All other units except the dynamo and battery, e.g. lamps, Klaxon, lighting, relay circuit, etc., would be earthed at their negative sides at the nearest point, but the dynamo and battery would not be. X.3082 X.3034 X.3348 (handwritten, all crossed out) X.3644 (handwritten) The fact that the windings of the starter motor were alive with the switch off on 6 EX was a shop error, as both Mr. Day's drawing of the wiring and my rough diagram of connection, copy of which was handed to the shop, showed the main switch on the positive side of the motor. The fact also that the motor was fitted with C.M. instead of C.M.3. quality brushes was a shop error as I had given instructions some time back for all experimental motors to be fitted with C.M.3. brushes. So far as I know, the brush springs are the latest strongest type giving 9 lbs. pressure in the set up position, as these are now standard. (Footer, upside down) sent by GSD(N) (handwritten) R.R. 199 (250m 19-7-17) MP 180865 (printed) | ||