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 investigation into the failure of an ignition coil by examining its windings.
| Identifier | ExFiles\Box 47\4\ Scan074 | |
| Date | 25th September 1924 | |
| X.4178 To BY.{R.W. Bailey - Chief Engineer} from EFC. EFC2/T25.9.24. X.4079 - FAILURE OF IGNITION COIL 3TG3 EX 5-GII. Reference your EY7/H16.9.24, my assistant's report on the unwinding of this coil is as quoted below:- "The secondary winding has now been unwound from the "above coil for the purpose of discovering the break in "the winding. "No trace of anything unusual was observed in the "winding itself but in the joint between the end of the "primary and the beginning of the secondary was found "to be in a bad condition, the insulation being blackened "and charred all round the contact which was also dis-"coloured. "The fault is therefore considered to be a bad connection "between the primary and secondary winding." For your observation we are herewith returning to you the primary, showing where the charring has been taking place, due to the broken connection. EFC. | ||