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 performance data for a 20/25 Shunt Dynamo.
| Identifier | ExFiles\Box 62\3\ scan0379 | |
| Date | 31th July 1933 | |
| E.{Mr Elliott - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Wst. c. to By/RD. 86037 Hs{Lord Ernest Hives - Chair}/Wst.2/MA.31.7.33. 20/25 SHUNT DYNAMO TO R.R.Sch.344. We have now completed a number of tests on two of the above dynamos. The results shew this dynamo to give quite a good performance and particularly good commutation at high speed. The latter feature we attribute largely to the extra long brushes and longer commutator. There is still a big drop however in the maximum output for safe heating at maximum speed as compared with the output at minimum speed. The performance results are as follows:- Cutting in speed (hot) - 875 R.P.M. (Aver. of two). Max. output for safe heating. - 12.0 amps. Max. output for safe heating high speeds - 8.3 amps. (Aver. oftwo). Brush wear after high speed endurance test P .001" N .001" Weight of machine complete - 23 lbs. 10 ozs. We are going to try 16 SWG. wire for the armature conductors with a view to improving the output - heating characteristics particularly at high speeds and we will report on this feature later. Hs{Lord Ernest Hives - Chair}/Wst. | ||