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 continued testing of dynamo No.161, detailing comparative wear tests of standard and narrower brushes.
| Identifier | WestWitteringFiles\L\2Jan1924-March1924\ Scan83 | |
| Date | 14th March 1924 | |
| Contd. -3- EFC3/T14.3.24. It may be remembered that as reported at the time, dynamo No.161 similarly fitted with a 57 segment commutator and two coils per slot armature, was fitted to 30II in October last, just before this chassis was sent to W.W. The output setting of this dynamo was in accordance with our production test. It is suggested that Mr. H.{Arthur M. Hanbury - Head Complaints} might examine the condition of the commutator and brush gear of this machine. Further details may be gathered from the attached reports, the second of which deals with a comparative wear test of standard and narrower brushes running with this armature, the routine of the test being as described for other commutation bench tests reported, in which the dynamo was run with each set of brushes continuously over nights at each of three speeds, i.e. 1750 r.p.m., 2500 r.p.m. and 3500 r.p.m., in rotation, until the equivalent (total) of 2500 miles was covered; in addition the machine being run intermittently during day times for a total period of about 30 hours in each case. (controlled by mechanically driven start and stop switch). As regards the noisiness of the machine, as reported in our EFC4/T29.2.24, we have not been able to appreciate the expected improvement. EFC. | ||