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).
Page 3 of a dynamo testing procedure, detailing the final bedding of brushes and various load and speed tests.
| Identifier | ExFiles\Box 70\4\ scan0107 | |
| Date | 10th April 1929 guessed | |
| -3- Contd. circumferentially, and between the bottom of the holder and the commutator, do not exceed the specified amount; Also that the bedding of the spring on the bevel of the brush and of the brush on the commutator are O.K. Failing to quieten noisy brushes in this way, the armature should be removed and the commutator skimmed, before proceeding with the final running test. (4) Final bedding of brushes. With the end cover removed, the dynamo shall now be run on load at 1300 r.p.m. for 3 1/2 hours charging at a voltage of between 17.5 and 18.0. This should render the brush bedding finally satisfactory. (5) At the termination of the above run, observations shall be made of the output of the machine at this same speed of 1300 r.p.m. which output should lie between 13.0 and 14.0 amperes, the terminal voltage being adjusted to 18.0 +/- .1 (6) With the dynamo still in the same hot condition it should be verified that running on open circuit it shows a voltage of at least 13.6 at 600 r.p.m. (7) The dynamo shall again be run on load and its speed varied up and down with a view to testing for mechanical and electrical noise. (8) The dynamo shall now be run up to 3600 r.p.m. still on load, and shall show no abnormal brush sparking. Further, the mechanical vibration due to any want of balance shall not be excessive. Sheet 4 | ||