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).
Load and output requirements for a dynamo battery system, arguing against a proposed two-rate charge switching scheme.
| Identifier | ExFiles\Box 163\6\ img104 | |
| Date | 19th December 1930 | |
| X6016. EFC. from E.{Mr Elliott - Chief Engineer} c. Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. PN.{Mr Northey} Hs.{Lord Ernest Hives - Chair} Hy.{Tom Haldenby - Plant Engineer} EL/M19.12.30. X.8780 X.5780 DYNAMO BATTERY SYSTEM TWO RATE CHARGE SWITCHING. X.6016. Referring to the proposed one way inter-connection scheme (EFC1/AD12.12.30) we feel that the operation of the switches would be difficult for the ordinary chauffeur to understand, and also that we cannot afford to reduce the dynamo output with full load on. This load is made up as follows :- Head lamps............ 10.0 amps. Side and tail......... 1.5 " Ignition.............. 1.0 " Screen wiper.......... 1.25 " Instrument board...... .5 " ----------------- 14.25 amps. There is nothing that can be left out of this list except the instrument board light. The screen wiper is often required for hours at a time on long wet night journeys when the lights should be at their best. If we abandon the 2 charge scheme as we have it then it will be necessary to reduce the dynamo output, and as, at the moment, its maximum value (at 14 terminal voltage) is only 12 amps. (EFC2/AD9.12.30) this appears inadmissible. It is desirable on the other hand that the dynamo should shew a 'plus' charge with all load on (unless car going slowly) otherwise the headlamps will lose in illuminating power to an extent which can be fully appreciated when driving, and the battery will eventually run down if used for continuous night work in the country. R.{Sir Henry Royce} is not yet convinced that the dynamo itself need be enlarged, and in memo R1/M13.12.30 makes suggestions for increasing the output. With regard to the lower rate of charge there is no doubt that this must be set quite high to cover the conditions of town driving in the winter and to obtain sufficiently early cutting in. | ||