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 correction of a long-period vibrator regulator and auto-switch system on experimental cars.
| Identifier | ExFiles\Box 59\1\ Scan334 | |
| Date | 9th September 1928 | |
| Contd. -2- EFC/T9.9.28. It was pointed out that it was to some extent correct to look upon the device as a long period vibrator regulator. At this time, owing to the fact that we were only reducing to half charge, the difficulty of ordinary vibrator regulator action had not (except as already referred to) arisen, because there was not too much loss of magnetic traction immediately after the points first separate. Two units so arranged were put on experimental cars and comparative major and minor curves of output without and with the resistance in the field circuit were issued. In our EFC4/T22.1.27 we reported that two units had now been running for some time on experimental chassis and no suggestion of failure had been observed, but that there was a small point of slightly incorrect functioning which has now been corrected. This was "that as a result of the fact that the negative end of the auto switch shunt coil is connected to the A terminal of the distribution board, the phenomenon sometimes occurs that in running up the machine to excitation the auto-switch operates, due to the very temporary high voltage of the dynamo, and before the cutout operates, and causes reduced rate of charge on first starting up. This does not always occur, but is liable to do so as a result of the voltage required to operate the auto switch through its shunt coil not being greater to a sufficient extent than the operating voltage to which the cutout is set. Before the cutout has had time to operate, the temporary high voltage of the dynamo is effective on the auto switch | ||