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).
Continued report discussing field currents and vibrator control systems, comparing carbon contacts to metal contacts in dynamos.
| Identifier | WestWitteringFiles\E\August1920\ Scan7 | |
| Date | 17th August 1920 | |
| Contd. -4- EFC4/T17.8.20. hot condition than for the cold as would be expected, owing to the higher voltage required to push the same current through the solenoid. Curves of field currents for the cols and hot conditions are also shown and it will be seen how these bend over before the vibrator begins, owing to the resistance of the carbon contact increasing with the fall of mechanical pressure. There is also no abrupt change in the slope of the field current curve at the point at which control begins. The function of the second coil of resistance 141 ohms is to improve the steadiness of operation of the vibrator. It would be perhaps worth while taking similar curves with this coil cut out of circuit or alternatively placed directly across the main voltage so as to directly assist the 88 ohm coil. This we shall probably do sometime, as we think it advisable to thoroughly study the different systems of vibrator control. We have yet to complete curves of this dynamo and regulator under load conditions, but these we hope to make the subject of a separate report. X.3860 We feel that this particular system of control is very interesting to us at the present moment as it seems that the use of carbon contact in place of metal contact introduces a certain steadiness of operation which seems to be absent, so far as we have gone with vibrator sets with metal contacts such as the Bijur, but we have a long way yet to go with these others to be able to say anything very definite. EFC. (upside down text at bottom) R.R. 199 (2501) (SD676 19-7-17) MP 180865 | ||