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).
Specifications for tumbler switches and green lamp switch units.
| Identifier | WestWitteringFiles\S\March1928-May1928\ Scan061 | |
| Date | 30th March 1928 guessed | |
| -3- Contd. necessity and complication of prolonging the armature contact to the M & B position. (3) Additional tumbler switch for earthing the magneto for testing the battery ignition, with indicating plate on front of dash. (4) Green lamp switch unit. The switch contacts with the green indicating lamp in series will be connected between the ammeter side of the main battery fuse and earth, so that the lamp will not become burnt out by a discontinuity in the dynamo-battery circuit, unless this is in the main fuse or battery itself. (5) Standard water temperature indicating lamp with green glass in place of red, to work in conjunction with green lamp switch unit. In this case, as in the case of the water temperature, the bulb is one of 16/18 volts, which is more satisfactory for these purposes than the ordinary 12/14 volts. Regarding the operating coil of the green lamp switch, its positive terminal is, together with the positive terminal of the cutout shunt coil, connected to distribution box terminal B, so that it will include in its warning indications the case of a discontinuous dynamo armature fuse when the field fuse is intact, a condition which we have pointed out as resulting in over-voltage of the dynamo, the field circuit being supplied by the battery. It will be remembered that we have suggested that the cutout shunt coil should better be connected to distribution box terminal C, in which case the positive end of the green lamp switch coil coulx and would also probably be better connected to C. Contd. | ||