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).
Letter to The S.U. Company inquiring about a heavy current draw issue with new electric petrol pumps when the engine is stationary.
| Identifier | ExFiles\Box 27a\2\ Scan130 | |
| Date | 9th February 1933 | |
| 12677 Hs{Lord Ernest Hives - Chair}/Wst.3/AD. February 9th, 1933. The S.U. Company, East Works, Bordesley Green Rd. Adderley Park, Birmingham. Dear Sirs, S.U. Electric Petrol Pump. With reference to the two S.U. electric petrol pumps of a new type which you have sent along to our Mr. Robotham for fitting to one of our experimental chassis, we note that when the engine is stationary there is a heavy current flowing through the windings of these two pumps. This suggests that it is possible for a condition to arise with the engine stationary where the trip contact operated by the pump solenoid is not opened and current flows direct from the battery through the windings to earth without any consequent motion of the pump. For instance, on the car in question with the two pumps wide in parallel, a discharge of 8 amperes was noted with the engine stationary and the pump switched on. We should like to have your views on this matter and whether you can offer an explanation for the phenomenon in question as obviously it is a serious matter if these pumps are inadvertently left switched on with the engine stationary. Yours faithfully, FOR ROLLS-ROYCE LIMITED. | ||