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).
Modifications to the charging and ignition system, including observations from road tests.
| Identifier | WestWitteringFiles\Q\February1927-March1927\ 91 | |
| Date | 15th March 1927 | |
| Contd. -2- EFC2/T15.3.27. considered not so much a means of switching off the charge during running as of switching off the system when finished with, and the three 'on' positions could be considered as the three ignition positions, one for running and two for testing, very largely irrespective of charging considerations. That is to say, there would not be the difficulty of running only on battery ignition when we switch off the charge because it would not be necessary to switch off the charge. While there is a charging switch, there is no need for flexible contacts as referred to in our EFC4/T28.1.27 because the negative end of the volt coil of the auto switch can then be taken to the frame, as suggested for the voltmeter and as we have now done for the auto-switches on the chassis. This alteration has enabled these to work in exactly the intended manner. Observations have been made on the road and the action is now precisely as at first anticipated. If the battery has been partly discharged, full charge is given until the voltage reaches the value 16.0 (hot condition) at which instant the auto-switch armature is pulled over and the resistance inserted in the field circuit. The output of the dynamo is reduced to about half of its previous peak value, and is now only reduced with speed by a relatively small amount as compared with a normal output curve. The curve of reduced output is, as illustrated by curves already issued, more nearly level, due to the effect of the ballast resistance used. [Stamped over last paragraph] REFERENCE ONLY [Handwritten bottom right] EHC 9012 [Printed bottom left] WB{Mr Brazier/Mr Bell} 225 (50M 2/26) (B.M. 257 26) (P.S. MS 30384) | ||