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 for a Speed Indicator Tester Motor, including flux, frequency, and turns per volt.
| Identifier | ExFiles\Box 33\5\ Scan062 | |
| Date | 5th February 1925 | |
| X1807 5.2.25. SPEED INDICATOR TESTER MOTOR. X1807 Assumed B = 9000 Gross C.S. Area = .80 sq." Nett. C.S. Area = .65 sq." Maximum flux = 6.45 x 9000 x .65 lines = 37700 lines. Frequency = 50.1 Since E = (4.44 Ø f T) / 10^8 Turns per volt = T/E = 10^8 / (4.44 x 37700 x 50.7) = 11.8 For 20 5 volts we want 2420 turns. Say 2500 turns. EFC. | ||