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).
Tests conducted on ignition coil insulating papers for secondary winding insulation.
| Identifier | ExFiles\Box 61\1\ scan0134 | |
| Date | 10th October 1930 | |
| X6110 By.{R.W. Bailey - Chief Engineer} from EFC. c. Sft{Mr Swift}/Mr.Brock. EFC4/ADL.10.10.30. X6110 (Strikethrough) X.1109. (Strikethrough) IGNITION COIL INSULATING PAPERS X.8712. FOR SECONDARY WINDING INSULATION. As requested in Ry/RD2/W24.9.30 we have tested the various samples of paper therein referred to together with a further sample of plain untreated white paper which Mr.Brock dried and impregnated with paraffin wax. The tests consisted of :- (a) Electrical breakdown test on the H.T. transformer. (b) Leakage conductance tests at various temperatures. The thickness of the various papers vary from .0005" to .0015" so for comparative tests in the (a) case a number of thicknesses of each paper was put together to make up .0045" for the test. In the (b) case the test thicknesses were similarly made up to .017". With reference to the actual tests, my assistant's report WE.30 reads as follows :- "with reference to (a) the following figures were obtained at atmospheric temperature :- Paper tested. Peak breakdown volts for .0045" Ditto per mil. Std. wax/paper 8440 1874 Plain white paper impregnated by EJB. with paraffin wax. 7700 1710 Plain paper unwound from coil after the coil had been wax impregnated. 6430 1433 Delco-Remy wax paper taken off condenser. 6680 1484 As regards the conductance test (b) the following results were obtained :- | ||