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).
Calculations and possible design reductions for EAC starter motor poles.
| Identifier | ExFiles\Box 64\1\ scan0199 | |
| Date | 15th January 1925 | |
| Y620 15.1.25. X.8620. EAC. STARTER MOTOR POLES. Reference EFC5/T15.9.24. EFC's original calculations were based on a rectangular cross section of 2.45" x .940" = 2.30 sq. ins. It has been confirmed (with RD.) that only one ^type of pole has been made & the instructions for which are embodied in D.70327, as below:- [Diagram of a motor pole with dimensions 1.800", .475", .475"] The table of possible reduction is as follows:- Stage. End radius. Centres. C.S. Area actual. Per cent. 1. .475 1.800 2.419 ✓ 100 The only pole D.70327 made. 2. .450 1.700 2.166 ✓ 90 3. .425 1.600 1.927 80 No. 2 is the type ultimately decided upon. EFC/EAP. | ||