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).
Continuation of dynamo testing procedures, detailing load, voltage, and performance checks.
| Identifier | ExFiles\Box 51\1\ Scan359 | |
| Date | 5th March 1924 guessed | |
| -2- Contd. Note:- Before taking this reading, the dynamo should momentarily be speeded up so as to reach an open circuit voltage of about double the voltage at which it operates normally. (4) The dynamo shall be run on load for 20 minutes at 1450 r.p.m. charging a twelve volt battery of ample capacity, at the end of which time the output shall not be less than 11 amperes, the dynamo terminal voltage being not more than 14.8. If the output falls short of this amount, first ascertain that the control brush is properly bedded to the commutator, it being assumed that the commutator is running clean. If no improvement can be effected this way, then the control brush must be retarded sufficiently to increase the output the required amount, and in so doing care is necessary to see that the correct bedding of the brush is not interfered with. (5) When correct as regards (4), it should be verified that the dynamo after 20 minutes run as in (4) shows a voltage on open circuit of at least 13.6 at a speed of 700 r.p.m. (6) 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. (7) The dynamo shall now be run up to 3600 r.p.m. still on load, and shall now show no abnormal brush sparking. Further, the mechanical vibration due to any want of balance shall not be excessive. | ||