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).
Test procedures for motor brushes and intermittent load performance.
| Identifier | ExFiles\Box 62\1\ scan0187 | |
| Date | 24th October 1933 guessed | |
| -6- During the last minute of the test the torque shall be at least 900 lb-inches. The speed shall not be less than 810 R.P.M. with a motor terminal voltage of 9.0 ± .1. (10) BRUSH TEST. With the motor running under the same load conditions as in the load test, each side by side pair of brushes should be lifted off the commutator in turn, in which circumstances the other pair of brushes diametrically opposite have to carry the full current. If they do this without showing signs of distress, which would be indicated by a jumping of the ammeter needle, they may be considered O.K. The others in turn may be proved to be O.K. in a similar manner. (11) INTERMITTENT LOAD TEST. Still with the same brake load applied, the motor shall be switched on and off for several times in succession. It should be on and off for about 5 seconds each alternately for a period of 3 minutes. During the test the motor should be observed for satisfactory engagement, general running particularly noisiness, and disengagement, also in particular the commutator and brushes should be watched. | ||