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).
Resistance measurements for the energising coils on High Pressure and Standard S.U. petrol pumps.
| Identifier | ExFiles\Box 146\1\ scan0237 | |
| Date | 8th April 1938 | |
| 1245 also 1263 W/P - Sr/VA. Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems}7/JH.8.4.38. In reply to your query regarding the resistance of the energising coils on the High Pressure and S.U. petrol pumps. It should be bourne in mind that there is a non inductively wound resistance coil coupled in parallel with the solenoid winding. No.1. No.2. High Pressure Pump. ohms. Coil with resistance. 4.33 4.24 Coil alone 4.57 Not taken. Resistance alone. 93.2 - Standard Pump. Coils with resistance. 3.87 3.97 Coil alone. 4.05 Not taken. Resistance alone. 99 Not taken. It is not possible to measure the resistance of the coil or quenching resistance separately without dismantling the coil from the pot. From these two examples, in each case, there is a variation of .10 ohms. No resistance is specified on the drawings the number of turns are given for the H.P. pump and an overall weight is given for the standard bobbin. I shall be glad to give you any further information or help you may require. Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems} | ||