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 for a fixed conductance dynamo on a 20 HP car.
| Identifier | ExFiles\Box 165\6\ img021 | |
| Date | 28th June 1926 | |
| X5660 L2.1.26. 28.6.26. FIXED CONDUCTANCE DYNAMO TESTS. 20 HP. X.5660. Tests have now been carried out in accordance with EFC6/T12.1.26. Test 1a. Speed to maintain 18.0 volts on the distribution box terminals for various external conductances. Conductance. Dynamo r.p.m. Car m.p.h. 0 740 10.1 .25 835 11.4 .50 960 13.15 .75 1155 15.8 Test 1b. Open circuit volts and speed for 6 amperes field current. Speed 875 r.p.m. = 12.0 car m.p.h. Distribution box volts 22.8. Test 2. Minimum conductance to restrict dynamo voltage to 18.0. This was found to be .865, the main amperes being 15.6. In each case above the machine was cold in order to produce the extreme conditions required. For hot condition minimum conductance was found to be .66 mho. Main amperes 12.0. Reading indefinite owing to instability. EFC. | ||