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).
Failure and burnout of an ignition coil on chassis 101-UF.
| Identifier | ExFiles\Box 69\1\ scan0231 | |
| Date | 8th October 1929 | |
| EFC. X8710 BY10/G.8.10.29. IGNITION COIL - CHASSIS 101-UF. We attach hereto the original of Hm{Capt. W. Hallam - Head Repairs}/AVS5/KW. 7.10.29. which represents the reply to a request on our part for more information in regard to the history of the car. Neither Mr. Davies nor myself see in the history any reason to cause the coil to fail by burning out the insulation, while on the other hand it is obvious that the coil has burnt out on the car, and therefore there must be some condition which is possibly abnormal by which it is possible to absolutely char the insulation of the primary winding on a coil which has the large section primary and 1¼ ballast, which represents our present standard equipment. This being so, I must say that I am thoroughly alarmed to find that this position is still possible, and consider that it is of the utmost importance that you should try and locate the conditions which have evidently caused the temperature of the coil to rise to such an extent as to burn out the insulation. We are very anxious to have a report on the position of the six coils which we have produced having a tubular base for the secondary winding, as we feel that the irregularity of the secondary winding in its first few layers is undoubtedly a very fruitful cause of failure. This matter is, however, an entirely different one to the points discussed above, and unless the trouble referred to can be located it would appear that even the later coil may suffer from being burnt out by the abnormal conditions which have caused failure of the coil under discussion. BY.{R.W. Bailey - Chief Engineer} | ||