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).
The methodology for observing 'balancing speeds' for Lucas and Smith chassis lighting dynamos.
| Identifier | ExFiles\Box 3\5\ 05-page160 | |
| Date | 4th March 1920 | |
| To R.{Sir Henry Royce} from Ck.{Mr Clark} c. to CJ. c. to E.{Mr Elliott - Chief Engineer} c. to Bn.{W.O. Bentley / Mr Barrington} c. to Wor.{Arthur Wormald - General Works Manager} c. to PN.{Mr Northey} c. to Dad c. to Hs.{Lord Ernest Hives - Chair} c. to Hy.{Tom Haldenby - Plant Engineer} X.295. CK{Mr Clark}2/T4.3.20. X.3014 - LUCAS E.575 TYPE CHASSIS DYNAMO. X.295. - SMITH (T & M) TYPE A & 2D DYNAMOS. We attach tables of observations of cutting in speeds of Lucas and Smith chassis lighting dynamos. These tables include the various observations of "balancing speeds" which we have made from time to time. Although we have called these "cutting in speeds", we prefer to call them "balancing speeds" because they are speeds which are independent of the characteristics of the cut-out but merely depend upon dynamo and battery. With the dynamo in a given conditions as regards temperature, these speeds will be more or less according to the E.M.F. of the battery at the time. With the battery in a given condition, the speeds will be more or less according as to whether the dynamo is hot or cold. All the observations are taken by adjusting the dynamo speed until the needle of the ammeter between the dynamo and battery is just round about zero, the battery being at the instant just "floating" on the dynamo; at this instant the E.M.F. of battery and dynamo in opposition is taken and recorded. The hot figures given in the temperature column are merely comparative and are taken with a thermometer, Contd. | ||