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).
The Goshawk dynamo's output performance, including experimental curves and comparisons with other machines.
| Identifier | WestWitteringFiles\J\January1923\ Scan32 | |
| Date | 23th January 1923 | |
| To R & E.{Mr Elliott - Chief Engineer} from EFC. c. CJ. & PM. c. HY.{Tom Haldenby - Plant Engineer} & RP. c. RG.{Mr Rowledge} & DE. ORIGINAL EFC2/T23.1.23. X.4383 - GOSHAWK DYNAMO OUTPUT PERFORMANCE. ------------------------------------------ As stated in our EFC2/T7.12.22, herewith now please receive photostat copy of experimental curves of output performance of two standard RR. Goshawk dynamos. As mentioned in the above report these curves are taken with the dynamo mounted on the new rig on which the dynamo is clamped between cast iron blocks to a cast iron table, so that the dynamo cannot attain the same temperature as previously. The new curves of specified performance which has been increased to correspond to the new method of mounting is given. Also two comparative curves, one each of the U.S.A. Bosch and C.A.V. DB{Donald Bastow - Suspensions} machines, with control brush fully retarded in the former case and in maker's setting in the latter. It is thought that these will be of comparative interest. It will be noted that their cutting in points are a good deal earlier though the outputs are smaller. Another photostat sheet showing the open circuit volt-speed curves of the same machines, both in the cold and hot conditions, and a table of the balancing speeds and ranges for and between the cold and hot condition are also given. It will be noted that the field currents of the RR. machine are relatively rather high, and though the size of field wire used as seemed to be the correct one as indicated by the calculations, nevertheless for this reason it has been arranged to make up a set of field windings of 20 SWG. for comparative | ||