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).
The comparative tests of varnished and waxed insulating papers for ignition coils and condensers.
| Identifier | ExFiles\Box 24\2\ Scan303 | |
| Date | 8th July 1929 | |
| By.{R.W. Bailey - Chief Engineer} from EFC. c. Roy.{Sir Henry Royce} X1109. EFC2/AM.8.7.29. X.1109. VARNISHED AND WAXED INSULATING PAPERS FOR IGNITION COILS AND CONDENSERS. We have now completed the third and last series of comparative tests on the three groups of insulating papers namely - (1) Standard varnished paper (American source) (2) Messrs. Symons varnished paper. (3) " " waxed paper. Two previous reports have been issued - EFC3/T9.5.28 with attached report PD24. EFC3/T7.6.28 " " " PD26. The first of these dealt with high pressure D.C. tests up to 9,500 volts with temperatures up to 150°C. The general conclusion of this was that Symons paper shewed up equally good, or even better than our present standard electrically, and we gave the recommendation that in the case of the Symons varnished paper this was worth prolonged experiments on ignition coils and condensers. The second report dealt firstly with a similar test, but in this case after repeated heating, and secondly with dielectrical breakdown tests both before and after heating. The results confirmed our previous conclusion that the Symons paper was undoubtedly the best electrically. contd. | ||