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).
Investigation report into a faulty customer dynamo from chassis 99MC that was overheating and throwing solder.
| Identifier | ExFiles\Box 70\3\ scan0305 | |
| Date | 29th August 1927 | |
| RR 238 (150 BKS.) (DB{Donald Bastow - Suspensions} 431-8-12 24) MP 306975 X878320 ROLLS-ROYCE LTD. INSTRUCTIONS. To: E F C Order No.: P.D.2 Customer's No.: X 8783 Aug. 29th 1927 Customer's Faulty Dynamo O.R. 75. off Chassis 99 MC. The above machine was sent to us with a complaint of solder having run. This is the second time that this machine has been sent to us on account of it having thrown the solder from the commutator connections. On the previous occasion (see EFC 2/T4-1-27) there was evidence to show that the failure was due to bad contact at the cutout points. Amongst other things, it was found then, that the machine had the early control brush setting of 120°. As the result of an investigation this time, we find that the machine still has the early C angle of 120°, and we can only conclude that melting of the solder was brought about by overheating, as the result of excessive output, due to this control brush position. It appears that, at the moment of the solder being thrown, a break occurred in the armature winding, due to an Signed Cont'd.{John DeLooze - Company Secretary} This Sheet must be filed on completion of the work. | ||