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).
Letter detailing an investigation into electrical faults, specifically battery ignition points and lamp bulb failures on a Phantom chassis.
| Identifier | ExFiles\Box 70\3\ scan0167 | |
| Date | 2nd June 1926 | |
| COPY. Moreton, Holly Place, Hampstead, N.W.3. To RR D/AWS2/B1.6.26. 2.6.26. Dear Sirs, In reply to your letter of yesterday. The letter referred to relates to suggested cause for battery ignition points pitting and burning out after under 1000 miles running. Also to lamp bulbs burning out and going black after a few hours use on my Phantom chassis. I suggested to Mr. Northey that the cause was excessive voltage generated by dynamo, causing a very strong back E.M.F. This letter contains results of exhaustive tests made with Weston instrument, known to be O.K. with Peto & Radford and C.A.V. accumulators connected up in order to eliminate the accumulator being the cause. I have since writing conducted other tests with different instruments, as Mr. Northey questions the accuracy of Weston voltmeter in his letter replying to mine, and still get the same results, viz. 2.5 volts per cell .15 volts when dynamo field circuit is broken rising to 2.9 volts per cell, 17.5 volts, almost immediately dynamo is put into circuit. Personally I am quite convinced as to the cause of this trouble and that the only cure is to so alter the dynamo as to stop this very excessive rise in voltage, | ||