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).
Summary of research into the causes of excessive leakage in battery ignition condensers.
| Identifier | ExFiles\Box 165\5\ img112 | |
| Date | 3rd August 1933 | |
| 46032 E.{Mr Elliott - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Wst. c. to Wbr. c. to By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to PH. R.R. BATTERY IGNITION CONDENSERS. We have been carrying out a detailed research on our standard condensers with a view to ascertaining the cause of the excessive leakage with this type of condenser. This leakage considerably lowers the effective voltage available at high temperature on the ignition system. Our investigation can be summarised as follows :- (1) The majority of the leakage is caused by the squashing of the condenser. This causes the wax on the paper to crack at the bends thus destroying the high dielectric properties of the paper. If we must persist in squashing our condensers we must wind them with plain paper and wax impregnate after squashing, but we are doubtful if, after the flattening process, we could introduce the wax at the bends with ordinary impregnating methods. (2) our The next source of leakage of a minor character is our standard practice of wrapping the condenser with tape. This should be discontinued in favour of oilsilk which gives less leakage. (3) The use of leatheroid to insulate the condenser from the case also introduces extra leakage. A piece of micanite moulded to shape would be better, or a piece of thick oil silk. | ||