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).
Overheated Dynamo (TP.55) from chassis 1-LC, which has thrown solder from its commutator connections.
| Identifier | ExFiles\Box 70\3\ scan0237 | |
| Date | 9th April 1926 | |
| X878320 To BY/HM.{Capt. W. Hallam - Head Repairs} from EFC. EFC4/T9.4.26. RE DYNAMO TP.55 EX CHASSIS 1-LC. This machine has been duly examined and we find that it has become somewhat overheated and thrown the solder from the commutator connections. Otherwise it does not appear to have any fault. There does not appear to be any reason for suggesting that there has been an open circuit, but we think the dynamo has, by a chance combination of circumstances, become sufficiently overheated in normal running just to allow the solder to run. The condition of the commutator appears to be quite good, except for one or two marks, the presence of which would be easily explained by effects subsequent to melting of the solder. Although the brushes appear to be in fairly good condition, it may have been the case that the control brush was making contact rather better on the side which would put up the output. In any case the machine is one with 120° control brush angle, which machine will have a higher output on the average than those we are now turning out with the 122° angle. I do not think we can do less than replace this machine free of charge. We return the dynamo herewith. It occurs to us, however, that we might reasonably use solder of a little higher melting point EFC. than we do use, and still have the condition that the running of the solder is the first damage through overheating. | ||