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 various output curves for a 20 HP dynamo against RPM and chassis speed.
| Identifier | WestWitteringFiles\U\January1930-April1930\ Scan011 | |
| Date | 2nd January 1930 guessed | |
| 20 H.P. AMPERE OUTPUT APPROX. OPERATING VOLTAGE 18.7 18.5 18.3 18.1 17.9 17.7 17.5 17.3 17.05 16.8 16.5 16.2 15.9 15.55 15.2 14.8 14.4 14.0 OUTPUT OF STANDARD DYNAMO AT FULL CONTROL BRUSH RETARD. D.8.A. 8° 118° 80°C. ESTIMATED PERMISSIBLE OUTPUT OF DYNAMO SUBJECT TO MANUALLY CONTROLLED CHARGE REDUCER INTER CONNECTED WITH HEADLAMP SWITCH. 8° 120° 80°C. REPRESENTATIVE OUTPUT CURVE OF STANDARD 20 H.P DYNAMO AT 80°C. SPECIFIED CURVE OF OUTPUT REQUIREMENTS - FOR 20 H.P. DYNAMO. OUTPUT OF STANDARD DYNAMO AT FULL CONTROL BRUSH RETARD. D.8.A. 8° 134° 80°C. DYNAMO R.P.M. CHASSIS M.P.H. 11/50 AXLE. 31.4 DIA. TYRES. | ||