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).
Starter motor drive ratios, voltage loss in circuits, and upcoming matters concerning the EAC gearbox and clutch.
| Identifier | WestWitteringFiles\J\February1923\ Scan22 | |
| Date | 11th August 1920 | |
| R.R. 285A (100 T) (S.H. 159, 11-8-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2800 (2) equivalent to that of a main winding of the machine. It was also thought that with the motor on teaser circuit for the slow running, two volts would be lost in the armature, four volts would be lost in the auxiliary electro-magnetic circuits, leaving six volts available for the teaser field winding which would make the resistance about ½ ohm. The ratio of the starter motor drive to the engine was fixed by Mr. Royce at 32 to 1 over-all, the motor driving an 8 to 1 spur gear reduction through a 4 to 1 epicyclic. Mr. Royce thinks it advisable for Mr. Clarke to come down to WW. to see us on this question as soon as we are ready, but this will not be just yet as there are a number of urgent matters on the EAC. gearbox and clutch to be disposed of. Will you kindly pass this information on to the right quarter. E.{Mr Elliott - Chief Engineer} [Signature] | ||