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 report on an experimental 20/25 HP dynamo with modifications, noting its unfavorable performance compared to the standard machine.
| Identifier | ExFiles\Box 62\3\ scan0213 | |
| Date | 10th April 1931 | |
| RR 238 (150 BKS.) (DB{Donald Bastow - Suspensions} 461-8-12-24) MP 306975 X6106. ROLLS-ROYCE LTD. INSTRUCTIONS. To H.K. Order No. Customer's No. 10 April 1931 Experimental 20/25 h.p. Dynamos We have now made a test on the 20/25 dynamo, in which the difference from standard consists in larger core slots and one gauge heavier armature winding, the smaller teeth being compensated by using an air gap of .012 instead of .015. The object is to reduce resistance losses in the armature and thereby obtain a higher output. The result of the test is not very favourable. Under standard test conditions, the cutting-in speed is 835 rpm (12 mph) compared with about 700 rpm (10 mph) for the standard machine. The maximum output is only about Signed (cont-d) | ||