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).
Specification for the electrical operation of a dynamo for the R.R. Goshawk (12 Volt System).
| Identifier | ExFiles\Box 39\2\ Scan065 | |
| Date | 21th April 1921 | |
| X 3533 EFC/T21.4.21. X. 294. SPECIFICATION OF ELECTRICAL OPERATION OF DYNAMO FOR R.R. GOSHAWK. X.3533. X.4259. (12 VOLT SYSTEM). The dynamo, after being run on load on the bench for four hours with an ambient temperature not less then 15°C and at a speed continually adjusted to secure maximum ampere output, and operating on a battery at a dynamo terminal voltage not less than 13.8, shall comply with the following :- (1) The temperature of the metal of the carcase, as measured by the insertion of a thermometer bulb in a little metal oil bath in good metallic contact with the carcase, shall not exceed 85°C. (2) The open circuit voltage of the machine immed-iately after this shall exceed 13.4 at a speed of 630 r.p.m. (3) The output in this same hot condition shall exceed 7 amperes at an operating terminal voltage of 14.5, for the speed range 1100 to 1850 r.p.m. and shall attain a value of 8 amperes at some speed in this range. (4) Above 1800 R.P.M. the ampere output may progress-ively fall to not less than 4½ amperes at 3500 R.P.M. NOTE:- Car-miles-per-hour-at 630 r.p.m. of dynamo corresponds to 10 miles per hour. EFC. | ||