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).
Test results and analysis for field resistance and peak machine output, including a data table.
| Identifier | ExFiles\Box 68\4\ scan0307 | |
| Date | 8th December 1924 | |
| RR 238 (150 BKS.) (DB{Donald Bastow - Suspensions} 461-8-12-24) MP 306975 ROLLS-ROYCE LTD. INSTRUCTIONS. To __________ Order No. __________ Customer's No. 2 The results are shown below. Field resistance | Volts | Amps | Ohms | Watts | Main Amps | |-------|-------|------|-------|-----------| | 3.3 | 2.72 | 1.21 | 8.98 | 11.5 | | 4.05 | 2.5 | 1.62 | 10.12 | 10.5 | | 4.9 | 2.25 | 2.18 | 11.03 | 9.4 | | 6.05 | 1.9 | 3.18 | 11.5 | 7.9 | | 6.05 | 1.8 | 3.36 | 10.9 | 7.4 | Interpolating from these results, the resistance necessary for the maximum dissipation would be 2.9 ohms when the watts dissipated would be 11.5. The peak output of the machine would then be about 8.5 amperes. Full particulars of the speeds at which these conditions occur were not taken but the maximum field current was reached soon after cutting-in and the peak output was reached at high speed, 3000-3500 r.p.m. Signed: J.A. This Sheet must be filed on completion of the work. | ||