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).
Examination report of an N.B. Dynamo J after a 10,000 miles test.
| Identifier | WestWitteringFiles\Q\December1926-January1927\ 56 | |
| Date | 27th November 1926 | |
| EFC. PC.120. EXAMINATION OF N.B. DYNAMO J.{Mr Johnson W.M.} AFTER 10,000 MILES TEST. In all this dynamo has run 21,354 miles between the dates 22.4.26 and 24.11.26. The insulation, tested on the A.C. mains was found to be O.K. The inner control and negative brushes were a little greasy and sluggish in the holders, but not seriously so. Some of the brushes have pieces chipped off them, but these have probably been damaged at some time when being removed for inspection, and are not sufficiently bad to affect the running of the machine. The surfaces of the commutator and brushes are in excellent condition, the wear of the brushes being:- Brush. Positive. Negative. Control. Inner. .026" .015" .023" Ou-ter. .021" .028" .043" The machine was given a run on the bench and its output and performance generally at a temperature of 80°C noted. It was quite satisfactory in these respects. Generally, the condition of the machine is very good. EFC/C.A.Pignatt. | ||