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).
Testing a special 16/18 V, 2.4 watt bulb for an electric thermometer and warning lamp.
| Identifier | ExFiles\Box 175\4\ img099 | |
| Date | 27th October 1927 | |
| EFC. 27.10.27. ELECTRIC THERMOMETER AND WARNING LAMP. Special bulb for warning lamp .16/18 V.{VIENNA} 2.4 watt. Chassis 8-EX and 12-EX have been fitted with the above type of bulb and have successfully completed the following mileages to date :- 8-EX - 1,640 miles. 12-EX. 2,515. In addition to normal running conditions a special test was carried out on 8-EX in which the car was run for four hours with the water temperature at 98ºC, the warning light being alight during the whole of that period. The object was to ascertain whether the contacts in the thermometer would stand up to continuous use when this type of bulb was used; previously, when using the 12-14 V.{VIENNA} 2.4 watt bulb, the electrical contacts fused under these conditions. The light given by the 16-18 V bulbs is slightly less than the 12-14V but is still sufficient for its purpose. A.J.Lidsey. | ||