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 car's electrical lighting system, voltage regulation, and a proposal for testing a new constant voltage system.
| Identifier | ExFiles\Box 61\2\ scan0084 | |
| Date | 27th October 1914 | |
| -2- R10/IB271014.Contd. The voltage, however, should not rise sufficiently high that if only one portion of the lamps on the car are switched on, it is sufficiently high to break the lamps and it is an excellent thing to have the side lamps and the tail lamps on one switch, and the head lights on another switch, and it does not seem that you need more than two switches, for the whole of the external lighting of the car. This has the advantage that one light need not be put on at a time in case, with a system like we propose, the voltage regulation of the dynamo was not exactly constant. I should be glad to know from Mr. Ellis what voltage the lamps will stand for a reasonable length of time above their normal 12 volts. A small side lamp could be the size to test, that is, would it stand say, 18 volts instead of its proper 12, for one hour. so It is rarely that the system is required to work without the battery that a pure constant voltage job does not seem very much needed, but we can see it would be beneficial to the working of the automatic switch, and also in a measure it reduces the risk of over-charging and under-charging the batteries, I think this combination of an approximately constant voltage and a fairly constant current system would be most suitable and practical. To enable us to better judge of the above, I shall be glad if you will arrange to have chassis 3000 fitted with the Bijur set which we have in stock. This is a constant voltage system, and we shall have an opportunity of noting how the automatic switch works on this. | ||