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).
Instructions detailing the fault diagnosis and likely cause for a dynamo issue.
| Identifier | ExFiles\Box 47\4\ Scan192 | |
| Date | 29th June 1920 | |
| Order No. PC 71 (2) it was found to be feebly excited in the wrong direction. When testing the commutator after the coil connections had been lifted, high resistance leaks were found to exist between segments, the lowest in resistance being 100,000 ohms about. The dynamo, when resoldered, and run on the bench appeared to be alright; the output only being rather light; ie at the end of 20 mins., it was 14.1 amps. When run on maximum load for several hours, however, it did not appear to get unduly hot. From a consideration of the above, it seems most likely that the fault, loose armature connections through loss of solder, was due to the main circuit being broken or partly so. Point b however suggests that something like a battery connected up the wrong way and discharged through the dynamo, occurred. Signed CHP. | ||