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 the operational conditions for a main and auxiliary switch circuit.
| Identifier | ExFiles\Box 64\4\ scan0213 | |
| Date | 14th March 1929 guessed | |
| -3- Contd. The amperes at 10.5 volts through the main switch coil will be 10.5 / .843 = 12.5 The conditions as regards correct operation of this second circuit are there: (c) The main switch must be definitely operated (i.e. all contacts made) from the 'off' position by a current of 10.0 amperes, and in doing so it must also definitely operate, via the mechanical arm, the auxiliary switch in such a manner that without the assistance of the auxiliary switch magnet pull, the top contacts (copper and carbon) are definitely broken and the bottom contact (green circuit) made. (d) The combined main switch and parallel resistance current must be capable of being broken reasonably sparklessly. (e) When the main switch is operated, the main motor current is switched on and it must be considered that the available voltage drops to 9. The availaMe amperes through the main switch coil will then be 10.6 It is necessary therefore that the main switch be capable of definitely holding on with a pressure of 2 lbs. on the copper contacts with a current of 8.5 amperes through its coils, and still in such a manner that without the siassistance of the auxiliary switch coil the bottom silver contacts of the auxiliary switch are definitely | ||