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).
Report page detailing motor performance metrics and efficiency improvements with a table of results.
| Identifier | WestWitteringFiles\T\2July1929-December1929\ Scan081 | |
| Date | 4th June 1929 guessed | |
| -2- Amperes 150 Volts 9.0 E.H.P. 1.81 Motor torque 60 lb-inches Motor speed 870 r.p.m. B.H.P. (on brake wheel on spindle) .83 Efficiency .46 the B.H.P. and efficiency in this case not including the effect of the 15 2/3 : 1 reduction. On production motors tested on our crankshaft rig, using a brake on a large brake wheel at the front end of the crankshaft, and adjusting it and the applied motor terminal P.D. so as to give the motor 150 amperes at 9.00 volts the maximum, average and minimum brake torques, speeds, B.H.P.'s and overall efficiencies observed were in accordance with the following table :- | | Max. | Average | Min. | |---|---|---|---| | Brake torque | 1002 | 963 | 900 | | Motor speed | 882 | 843 | 810 | | B.H.P. | .88 | .83 | .74 | | Efficiency | .49 | .45 | .41 | from which it will be seen that owing to improvements in production, we now obtain, including the effect of the | ||