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).
The development of an electrical distribution unit, discussing dynamo charging, circuit protection, and experimental units.
| Identifier | ExFiles\Box 59\1\ Scan191 | |
| Date | 30th November 1927 guessed | |
| -2- Contd. might then not result in dynamo charge until the battery voltage fell sufficiently. This effect can be produced. When, however, only the headlamps are switched off, the load of the side and tail lamps is quite sufficient to delay the rise of voltage of the system long enough for the headlamps filaments to cool, and the auto switch does not have a chance of going over before the headlamp filaments become quite cold. We have, we think, carefully considered every possible circumstance and we cannot discover any further snag beyond the one that has already been mentioned of not giving (to the dynamo and cutout shunt coil only) complete protection from faults in that portion of the dynamo circuit through the cutout between the chassis frame and the surface of the commutator under the negative brush. It is impossible for electrical damage to occur to any unit as a result of one (only) break or bad connection anywhere else. The battery can be disconnected with impunity, and in emergency it would be quite possible to travel without a battery with a somewhat flickering light. x We are knocking up three units arranged in this way, mostly, of distribution board parts, two of which we shall get going on experimental cars. Ultimately, however, we feel that it would be your desire to have this unit incorporated in the distribution box. Accordingly we are sending you a blueprint of an electrical diagram of this imaginary distrib- ution box containing the auto switch unit in addition to the cutout, the external connections to this box being precisely as at present. We feel confident enough of the results to | ||