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).
Specification for modifying 40/50 and 20 HP dynamo armatures for greater output at higher speeds.
| Identifier | ExFiles\Box 68\4\ scan0086 | |
| Date | 25th April 1928 | |
| X8664 To BY.{R.W. Bailey - Chief Engineer} from EFC. c. BY/RD. EFCB/T25.4.28. 40/50 and 20 H.P. DYNAMO ARMATURES FOR GREATER OUTPUT AT HIGHER SPEEDS. X5663 Further to our EFC1/T23.4.28, we now confirm that 40/50 and 20 H.P. armatures should be proceeded with with the standard No. of 28 slots and windings diagrammatically exactly as standard, but in each case with three turns per coil in place of four of one gauge larger conductor wire, which therefore becomes 18 S.W.G. in the 20 H.P. case and 17 S.W.G. in the 40/50 H.P. case, the width and depth of each slot being altered accordingly. Armatures to this specification should be instructed as quickly as possible so that we may get some moving for the purpose of satisfying customers who require the higher output at higher speeds. EFC. | ||