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).
Inspection report on the condition of a dynamo, commutator, armature, and battery.
| Identifier | WestWitteringFiles\K\November1923\ Scan21 | |
| Date | 7th November 1923 | |
| Contd. -3- EFC4/T7.11.23. Dynamo. Generally speaking, the dynamo was found to be in good condition. The insulation of the machine was found to be O.K. with the exception that that of the positive brush was reduced due to accumulation of brush dust, and allowing a slight flash-over on 200 volts A.C. This, however, would be far from serious. The commutator surface was a good uniform light brown with no projecting mica. The condition of the brushes and brush holders was quite good in spite of the fact that the positive brush was found to be rather slack in the holder. The brush spring pressures were:- Positive 1.0 lb. Negative .3 lb. Control .4 lb. the last two, therefore, being rather on the low side. It was found that the four main brush holder securing nuts could each reasonably be given a quarter of a turn. In the case of the control brush holder, in one case the bolt rotated and so the nut could not be tightened up; in the other case, three-quarters of a turn could reasonably be given. There was only a moderate amount of dust deposited over the brush holders. The armature was found to be slightly stiff in turning and became quite easy by easing the end plate screws. This was thought to be due to a slight longitudinal tightness in the bearings. The armature connections to the commutator presented a rather untidy appearance, the cotton insulation being rather frayed. As regards the output of this machine, it was found to be somewhat high and needs re-setting before the machine is replaced. Battery. The battery has not yet been tested, but appears outwardly in good condition. | ||