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 results of losses tests on self-starter motor armatures.
| Identifier | ExFiles\Box 34\3\ Scan132 | |
| Date | 1st January 1917 | |
| R.R. 235 a (400 T) (S.C. 536. 15-2-15) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 1546. COPY. To EFC. from R.{Sir Henry Royce} c. to J.{Mr Johnson W.M.} c. to Na.{Mr Nadin} c. to By.{R.W. Bailey - Chief Engineer} c. to EP.{G. Eric Platford - Chief Quality Engineer} 4117 c. to EH. c. to Hy.{Tom Haldenby - Plant Engineer} c. to OY. c. to Wor.{Arthur Wormald - General Works Manager} for Mr. Ellis. COPY. R10/B1117. January 1st 1917. X. 2642. -LOSSES TESTS ON R.R. SELF)STARTER MOTOR ARMATURES. It appears from these experiments that the losses in the armature cores in the different designs are not enormously different, and therefore we can use the type which appears from other points of view to possess the greatest advantages. This, however, appears to be the one with 45 slots, tape wound, which, owing to its high flux and low internal resistance, is electrically the most efficient armature. Regarding the width of the brush contact, it will be found that in the next series of experiments, where we test the motor complete for efficiency, that the width of the brush will depend upon the type of brush used, which can be wider in proportion to the exactness of its location being correct. I believe it will be found that the brush contact can be wider than in the experiments just completed, which I think you would have found not nearly so bad had it been set in the correct neutral position, which it ought to have been. R.{Sir Henry Royce} | ||