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).
Brake test report for a Smith starter motor.
| Identifier | ExFiles\Box 51\5\ Scan129 | |
| Date | 10th October 1921 | |
| X. 43425 MOTOR FORM 5. X.3009 - BRAKE TEST OF STARTER MOTOR. Date:- 10-10-21 Motor under test:- Smith. Dia. of brake wheel = 10" No.:- Type S.S. Reduction gear ratio = - Weight of pan and portion of rope 5 lbs. 3 ozs. Load in pan (W) | Spring balance Reading (S) lbs.ozs. | Speed R.P.M. | Amps. | Volts. | W-S (lbs) | T-t (lbs) | Torque (lb-inches) | B.H.P | E.H.P. | Efficiency 8 | 1 15 | 190 | 160.7 | 8.78 | Slipping 6 1 | 11.25 | 56.25 | .17 | 1.89 | .090 7 | 1 11 | 400 | 154.5 | 8.91 | 5 5 | 10.5 | 52.5 | .33 | 1.85 | .178 6 | 1 6 | 540 | 147.5 | 9.05 | 4 10 | 9.81 | 49.05 | .42 | 1.79 | .235 5 | 1 4 | 672 | 138.5 | 9.23 | 3 12 | 8.94 | 44.7 | .48 | 1.71 | .281 4 | 1 3 | 820 | 127.7 | 9.44 | 2 13 | 8.0 | 40.0 | .52 | 1.62 | .321 3 | 1 0 | 955 | 120.5 | 9.59 | 2 0 | 7.19 | 35.95 | .55 | 1.55 | .355 2 | 1 0 | 1173 | 107.8 | 9.84 | 1 0 | 6.19 | 30.95 | .58 | 1.42 | .408 1 | 0 14 | 1400 | 97.0 | 10.06 | 0 2 | 5.31 | 26.55 | .59 | 1.31 | .450 0 | 0 13 | 1702 | 86.5 | 10.27 | -13 | 4.375 | 21.87 | .59 | 1.19 | .496 | ||