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).
Road tests of green lamp and auto switch schemes to check the consistency of their settings.
| Identifier | ExFiles\Box 59\1\ Scan329 | |
| Date | 13th July 1928 | |
| EFC. AD.10. X. 4008 13.7.28. X.4040. ROAD TESTS OF GREEN LAMP AND AUTO SWITCH X.4008. SCHEMES. Road tests to check the consistency of the settings have been made on 9-GIII and 12-EX green lamp schemes, and on 8-EX auto switch (old R.R. distribution board type). All three have the temperature compensated windings, that on 9-GIII having a manganin wire resistance coil. 9-GIII. (Switch H). Operated at 15.8 to 16.0 volts. This is lower than as set on the bench (16.8 volts). On slightly raising the setting, however, the switch would not close, the system voltage not rising appreciably above 16.0 volts. The battery negatives were not in perfect condition and the switch was re-set for the time being, as before, to avoid excessive gassing of the positive plates. 12-EX (Switch G). Operated at about 16.2 volts. This is lower than the bench setting (16.8 volts). It would sometimes close at 16.0 volts on bad road. The battery on this car is O.K., but the system voltage does not rise much above the closing voltage of the switch if the charge is left on continuously. Contd. | ||