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).
Voltage for side lamp bulbs and recommending fitting 14 to 16 volt lamps.
| Identifier | ExFiles\Box 166\4\ img135 | |
| Date | 21th April 1932 | |
| W/S. L.E. from Hs{Lord Ernest Hives - Chair}/Wst. c. EP.{G. Eric Platford - Chief Quality Engineer} MX.{John H Maddocks - Chief Proving Officer} c. EV.{Ivan Evernden - coachwork} X6089 Hs{Lord Ernest Hives - Chair}/Wst3/AD21.4.32. SIDE LAMP BULBS With reference to your LE4/C/15.4.32, we have given this matter our further consideration and we cannot see how we can possibly decrease the voltage available at the side lamps with the battery fully charged without putting in a small resistance unit in series with the lamps. This, we consider, would be impractical as the volt drop across the resistance would vary with the particular wattage lamp which any customer might fit. Our only recommendation is that customers should be advised to fit 14 to 16 volt lamps. We do not think there will be any difficulty with this arrangement as side lamps (properly rated) last a considerably length of time and a customer would usually carry additional spares with him in the car. Also, under normal night running when the battery would not be fully up, the brilliancy of the side lamps would not count for anything. With our present half charge scheme this high voltage on the side lamps appears to be inevitable. Hs{Lord Ernest Hives - Chair}/Wst. | ||