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 condition of a Dynamo D from chassis 4GII after running 5513 miles.
| Identifier | ExFiles\Box 50\5\ Scan296 | |
| Date | 4th March 1924 | |
| EFC. {E. Fowler Clarke - Electrical Engineer} AC.2. 4th March, 1924. X.4383 - DYNAMO D FROM 4GII. (STANDARD). This machine has run 5513 miles on the chassis and has now been replaced by dynamo 470. The insulation as tested on 200 volts A.C. is O.K. The brushes were well worn at the start of the run but have not worn much further, there being little dust deposited inside the cover. The spring pressures started at:- Positive .7, Negative .6, Control .3 (1b) and finished at Positive .6, Negative .35, Control .3 (1b) The positive brush surface is rather dull and the negative and control are moderately smooth, the control showing signs of having sparked, but when run on the bench there is very little sparking anywhere. The commutator is in very good condition, being a fairly polished light brown and uniform across the segments, the insulation having been machine undercut. The brushes are of Z material, with bevelled tops, the machine being representative of up-to-date standard production. EFC {E. Fowler Clarke - Electrical Engineer} /RJA. | ||