Technical memo discussing the circuit arrangement of a green lamp charge indicator and comparing it to the old Lucas system.
| Identifier | ExFiles\Box 65\2\ scan0018 | |
| Date | 4th January 1929 | |
| X7730 To R. {Sir Henry Royce} from EFC. {E. Fowler Clarke - Electrical Engineer} c. BJ. SG. {Arthur F. Sidgreaves - MD} c. Wor. {Arthur Wormald - General Works Manager} E. {Mr Elliott - Chief Engineer} c. EY. C. EFC {E. Fowler Clarke - Electrical Engineer} /T4.1.29 GREEN LAMP CHARGE INDICATOR. X.4040 X.7730 Referring to your R1/M26.12.28, we regret that we cannot understand the circuit therein given. If the cutout series coil and contacts are arranged to be on the switching or high potential side of the system, then it appears to us that they must be situated electrically between the charging switch and the load or distributing switches/in our switchbox, such an arrangement does not appear to be possible. A further point is that the cutout becomes a four-terminal unit. The arrangement in question is exe(Aero Engine)mplified in the old Lucas arrangement on the Silver Ghost(1907 40/50 historic RAC 15,000 miles trial) cars, where the positive of the system was the earthed or datum side, the positive of the dynamo being in direct connection with earth. All switching, both hand and auto, was done on the negative side. EFC. {E. Fowler Clarke - Electrical Engineer} | ||
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).