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).
Output performance of the 20 HP dynamo, including specified, actual, and engine-hot outputs.
| Identifier | WestWitteringFiles\L\2Jan1924-March1924\ Scan79 | |
| Date | 13th March 1924 | |
| To R.{Sir Henry Royce} from EFC. c. C.J. & PN.{Mr Northey} c. E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} c. Hy.{Tom Haldenby - Plant Engineer} EP.{G. Eric Platford - Chief Quality Engineer} ORIGINAL EFC2/T13.3.24. X.4383 - R.R. 20 HP. DYNAMO OUTPUT PERFORMANCE. Further to our EFC2/T3.3.24, and in parallel with our EFC1/T13.3.24 giving similar results for the E.A.C. dynamo, herewith now please receive photostat copy of sheet of curves of 20 HP. dynamo performance, comprising:- (1) The specified output (which it is desired should be exceeded at a running temperature just less than 75°C on the bench). (2) The actual output of the machine corresponding to the general specification, this being at 75°C. (3) The engine hot output (85°C), with the same control brush setting. (4) Engine hot (85°C) output with the production test setting of the control brush. This is supposed to represent the actual output in running conditions on the chassis. (5) The same engine hot output with the value of the ignition current at each speed subtracted. It will be seen :- (a) That the present standard 20 HP. machine readily complies with our specification of test. (b) That in this 20 HP. case, there seems to be more difference than in the E.A.C. case between the effect on the balancing speed of altering the control brush position. (c) That we have, as stated in our EFC2/T3.3.24, a considerable difference, namely of 2 amperes on the peak, between the actual setting for production purposes and the setting to give the maximum output that is considered O.K. from our laboratory tests. This gives a margin in favour of cooler running of the machine. Contd. | ||