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).
Comparative test results for a motor, with/without an epicyclic gear and with varying numbers of brushes.
| Identifier | ExFiles\Box 75\1\ scan0155 | |
| Date | 11th August 1920 | |
| R.R. 235A (100 T) (S.H 159. 11-8-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2500 -2- Comparative Test taken with and without epicyclic gear fitted to motor - no quantity of oil in gear. Resistance in switch .201 Ohms. | Test No. | Voltage at motor. | Amps. | Speed of motor. | Whether epic: gear fitted. | |---|---|---|---|---| | 1 | .3 | 36 | 940 | No. | | 2 | 2.7 | 37 | 800 | NO. | | 3 | 1.8 | 38.5 | 210 | Yes. | | 4 | 1.8 | 39.0 | 200 | Yes. | Comparative test taken without epicyclic gear and with two and four brushes in use. To show variation in speed due to friction of brushes. Resistance in switch .201 Ohms. | Test No. | Voltage at motor. | Amps. | Speed of motor. | Number of brushes. | |---|---|---|---|---| | 1 | 2.55 | 38 | 780 | 4 | | 2 | 2.5 | 38 | 760 | 4 | | 3 | 4.3 | 31 | 1660 | 2 | | 4 | 4.2 | 31 | 1740 | 2 | Hs.{Lord Ernest Hives - Chair} | ||