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).
Suggesting a change in headlamp bulb wattage from 60W to 48W to manage dynamo output and reduce battery discharge.
| Identifier | ExFiles\Box 166\4\ img088 | |
| Date | 1st September 1931 | |
| X6089 R.{Sir Henry Royce} from E.{Mr Elliott - Chief Engineer} c. Sg.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. PN.{Mr Northey} By.{R.W. Bailey - Chief Engineer} c. Hs.{Lord Ernest Hives - Chair} EFC. E1/M9.1.31. X.6084. DYNAMO OUTPUT X.6089. Before leaving Derby we suggested that the 60 watt bulbs in use on our headlamps should be replaced by 48 watt, not with a view to passing the trouble on to the customer but because we think the smaller power bulb with the ammeter shewing a 'plus' charge would give as much light as the 60 watt running with a battery discharge, and at the same time there would be less liability for the battery to be run down. Up till the beginning of last year the 36 watt bulb was our only official standard but it appears that at some time in May the 60 watt was included as an alternative on the list. It might be a good scheme to circulate a standardisation sheet for any alteration of this nature, and to set out in the instruction book a list of the bulbs that should be used throughout the electrical installation of the chassis. E.{Mr Elliott - Chief Engineer} | ||