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).
Graph showing the brake efficiency and performance characteristics of a Zenith starter motor during a brake test.
| Identifier | ExFiles\Box 35\4\ scan 109 | |
| Date | 3rd May 1921 | |
| STARTER MOTOR BRAKE EFFICIENCY REF. No. Z.S.710.B/4 DATE. 3.5.21 ZENITH STARTER ON BRAKE TEST Armature. No. 1. AXES LABELS AND SCALES: VERTICAL AXES (from top to bottom): R.P.M: 3000, 2700, 2400, 2100, 1800, 1500, 1200, 900, 600, 300, 0 B.H.P: 2.0, 1.8, 1.6, 1.4, 1.2, 1.0, .8, .6, .4, .2, 0 AMPERES: 250, 225, 200, 175, 150, 125, 100, 75, 50, 25, 0 VOLTAGE: 20, 18, 16, 14, 12, 10, 8, 6, 4, 2, 0 EFFICIENCY: 1.0, .9, .8, .7, .6, .5, .4, .3, .2, .1, 0 ELECTRICAL H.P: 4.0, 3.6, 3.2, 2.8, 2.4, 2.0, 1.6, 1.2, .8, .4, 0 HORIZONTAL AXIS: TORQUE (POUND INCHES): 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 LABELS ON PLOTTED LINES: R.P.M. B.H.P. AMPERES EFFICIENCY ELECTRICAL H.P. | ||