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).
Continued description of an electrical system fault involving the main switch, relay switch, and motor.
| Identifier | WestWitteringFiles\N\2October1925-December1925\ Scan146 | |
| Date | 18th November 1925 | |
| EFC2/T18.11.25. -4- Contd. whilst the main switch flicks off and on again. The main current is thus restored, but at the second contact of the main switch is of insufficient magnitude again to pull down the relay switch, then on the release of the push button switch, a reverse current travels from the main positive terminal of the motor backwards through the teazer winding and actuator box, through the relay contacts, then through the main switch coil and parallel resistance, and to earth through the actuator box contact. This current is of sufficient magnitude to hold the main switch on, but as previously stated, the main current which it causes to be sustained, is of insufficient magnitude to pull the relay switch off contact. Consequently the motor continues to turn the engine light. The system can, of course, be stopped by pulling off the main switch by hand (if the switch cover is off); it has also been ascertained that it requires the very lightest touch on the relay switch to break the contact and stop the system in that way. It is a question of the magnitude of the current in the heavy coil and the relay magnet core, and it is extremely unlikely that one can possibly run the car if the gears are left in accidentally. Then, of course, there is no fault if the engine starts. To correct this, it would appear that we should have to get a few more turns of heavy | ||