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).
Test results and failures of insulation in battery ignition coils.
| Identifier | ExFiles\Box 69\1\ scan0292 | |
| Date | 1st January 1930 | |
| X8710. By.{R.W. Bailey - Chief Engineer} from EFC. c. Sft{Mr Swift}/Mr Brock. EFC4/ADL.1.30. X.8710. BATTERY IGNITION COILS. Further to our EFC5/AD3.1.30. in the course of the tests we have been making on the two special coils handed to us wound with four turns of insulating paper between the first three layers and two turns only between the subsequent layer, we have had a failure in one case, viz. that of the coil with paraffin wax paper inter layer insulation, between the bottom two layers. In another case of a coil handed to us by Mr Brock in which the inter layer insulation consisted of only two layers of paper at every stage inclusive of the bottom layers, we have had a failure between layers half way up the secondary. It will be noted that the results we are obtaining in the various cases do not enable us to draw any definite conclusions owing to the insufficient consistency of the results. In regard to the actual voltage available from layer to layer on the secondary, we are preparing a scheme whereby we hope to be able to roughly measure these voltages and so determine, if possible, the amount and position of the maximum voltage per pair of layers. In the meanwhile the tests on the other one of the two coils first mentioned are in progress. EFC. | ||