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).
Review of two head light dimming devices, a C.A.V. series parallel switch and a 'REX' head light controller.
| Identifier | ExFiles\Box 61a\1\ scan0105 | |
| Date | 22th April 1921 | |
| R.R. 256A (100 T) (S.H. 798, 10-12-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2947 X4291 EFC3/T22.4.21. To R.{Sir Henry Royce} & E.{Mr Elliott - Chief Engineer} from EFC c. CJ. & PN.{Mr Northey} c. By.{R.W. Bailey - Chief Engineer} & Bn.{W.O. Bentley / Mr Barrington} c. Da.{Bernard Day - Chassis Design} & EP.{G. Eric Platford - Chief Quality Engineer} c. EWT. for R.R.Inc. X.4291 - HEAD LIGHT DIMMERS, AND IN PARTICULAR X.4843 - C.A.V. SERIES PARALLEL DIMMER SWITCH. X.4344 - "REX" HEAD LIGHT CONTROLLER. We have recently received two devices for head light dimming purposes. The first one of these is a small pull and push button series parallel switch made by the C.A.V. Company, which appears to be quite a reasonably well made switch, except for the fact that in loosening the terminal screws, the contacts are loosened as well, which might interfere with the operation of the switch through the contacts being out of place. When two 12 volt half watt type lamps, normally taking 2.0 amperes each, are placed in series, the volts and amperes on each lamp become 6 volts 1.5 amps., and the amount of dimming is considered to be just about correct. The other items is a "REX" head light controller, which consists of a drum which can be attached to the steering with an arm which is moved in order to operate the controller. The inside of the controller consists of a continuously adjustable resistance which is placed electrically in series with two head lamps in parallel. For further report on the working of the controller see attached sheet. It will be seen from this that the controller would apparently be better if the contained resistance was | ||