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).
Comparison between an auto charge control switch and a green lamp scheme for vehicle electrical systems.
| Identifier | ExFiles\Box 60\3\ Scan038 | |
| Date | 29th March 1928 | |
| 7.J.A. X 4040. 29.3.28. FURTHER POINTS OF COMPARISON OF AUTO CHARGE CONTROL SWITCH AND GREEN LAMP SCHEME. (1) Green lamp scheme requires for its proper fulfilment, in addition to the additional lamp unit, a hand operated field breaking switch, or alternatively, and as desired by R. {Sir Henry Royce} , special switchbox with M & B on the first position with additional earthing switch for magneto, this arrangement being the one put on 12-EX for the 10,000 mile test. In the green lamp scheme the sequence of operation is as follows :- System voltage rises to a pre-arranged figure, green lamp switch armature is drawn over, making contact whereby the independent (green) lamp unit is lit. The driver notices this light and has to switch off the charge by means of the appropriate switch. In the auto switch, the whole sequence of operation needs only one unit, instead of three units, and is entirely automatic. (2) It hardly occurs to us that the use of the auto switch unit throws any more responsibility on the makers than the use of the green lamp scheme. In the latter the responsibility of giving correct indications by means of the lamp still rests on the makers, and the means whereby this is done are the same means whereby the whole thing is done automatically in the auto switch. Or, put in another way, Contd. | ||