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).
Dynamo output characteristics and solutions for the 40/50 chassis electrical equipment.
| Identifier | ExFiles\Box 36\4\ scan 249 | |
| Date | 22th June 1922 | |
| X30146 Extract from EFC3/T22.6.22. X.4132. RE STANDARDISATION SHEETS FOR 40/50 CHASSIS ELECTRICAL EQUIPMENT. Y30146. X294 It will be remembered that the output curve of the Lucas E.57 generator does not fall appreciably with increasing speed, but 12 to 11 amps. is maintained if the charging switch be kept on, even at the high rates of speed obtained in country running in the daytime. The use of a dynamo with an output characteristic which falls somewhat with increasing speed, if the amount of falling off is not overdone, would appear to effect a slight improvement, but the amount of falling off has necessarily to be a compromise between the conditions of fast running in the day-time and fast running at night, in the latter case it being not desirable that the battery is discharging (to assist the dynamo with the load) at more than, say, 2 amperes. Such a compromise is being aimed at on the Goshawk. In passing, it has always appeared to us that so long as an inherently regulated dynamo is used, the most satisfactory all round solution of the problem, involving the greatest ratio of [s]achievement[/s] complication consists in the use of a resistance in the circuit which is automatically inserted in the field circuit of the dynamo when charge is put on without lights, but is automatically cutout when charge is put on with lights on, and in some of the Lucas systems, though not immediately adaptable to that of the 40/50; this feature is incorporated; this reduces the dynamo output when the lights are not required." | ||