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 performance and silencing of the Lucas E.575 dynamo.
| Identifier | ExFiles\Box 36\4\ scan 106 | |
| Date | 30th July 1920 | |
| B.B. Wks. (100 T) (S.G. 648. 19-5-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2518 To By.{R.W. Bailey - Chief Engineer} from EFC. c. Wd.{Mr Wood/Mr Whitehead} c. EP.{G. Eric Platford - Chief Quality Engineer} c. Wor{Arthur Wormald - General Works Manager}/Mr. Brock. X 3014-6. EFC4/T30.7.20 X.3014 - LUCAS E.575 DYNAMO SILENCE. Regarding the Lucas E.575 dynamo handed over to us from production for the purpose of comparing the out-put with the control brush in the "normal" and "retarded" positions, we find that in the "normally hot" working condition of the dynamo, the maximum output is reduced from 12 amperes to 9 1/2., the amount of motion on the brush corresponding to 1 1/2 commutator segments. We do not agree to a reduction of output in the hot condition to below 10 amperes, in other words, we do not agree to moving the control brush back from its "normal" position by an amount exceeding one commutator segment. The cutting in speed is not appreciably affected by this change. We do not know whether the point has been watched, but we would like to point out in case it has not, that on the production rig, having adjusted the dynamo to a certain speed so as to cause it to sing in with the brush in the "normal" position, the act of now retarding the control brush and reducing the output causes the speed materially to increase, in which case the hum might be dissipated from this secondary cause. It would, of course, be essential for the use of a speedometer to bring the speed back to what it was before Contd. | ||