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).
Specifications and testing of a green lamp switch unit.
| Identifier | ExFiles\Box 60\3\ Scan052 | |
| Date | 1st May 1928 | |
| X4040 EFC2/T1.5.28. To R.{Sir Henry Royce} from EFC. c. BJ. E.{Mr Elliott - Chief Engineer} c. Da.{Bernard Day - Chassis Design} By.{R.W. Bailey - Chief Engineer} c. Wor.{Arthur Wormald - General Works Manager} PN.{Mr Northey} GREEN LAMP SWITCH UNIT. X4040 Herewith we send you a diagram of the green lamp switch unit. The winding on the pivot bobbin is now Manganin in series with the copper winding on the armature bobbin. The resistance ratio is 5 Manganin to 1 copper, and the ampere turn ratio is 4 Manganin to 13 copper. In addition to the green lamp switch unit which we have reported to you as having been fitted to 12-EX, a second switch unit and lamp have now been made and tested, and are being fitted to experimental chassis 9-G3. Some data concerning this are given in my assistant's report AD.6. of which we attach a copy. EFC. | ||