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 data for Lucas dynamos and cut-outs, comparing performance speeds under hot and cold conditions.
| Identifier | WestWitteringFiles\D\March1920\ Scan49 | |
| Date | 16th March 1920 | |
| Contd. -5- Ck{Mr Clark}2/T16.3.20. approximate dynamo balancing speed corresponding to the battery E.M.F. specified, for the quite cold or fully hot condition as the case may be. These speeds are to be taken in comparison with the speeds in the fourth column and show how much later the cut-out operates when cold and hot then it should operate in the ideal case. Dynamo:- Lucas E.575 No.402. Cut-out:- Lucas "A". Condition. | Volts. | Amperes. | Speed. | Corresponding approx. dynamo balancing speed Cold. | 1. 12.2 | -- | } 620 | 600 | 2. 12.4 | -.5 | } | 3. 12.1 | -2.8 | } | 4. 10.5 | -- | } 560 | -- Hot. | 1. 16.0 | -- | } 820 | 740 | 2. 14.0 | +1.7 | } | 3. 13.1 | -2.6 | } | 4. 11.30 | -- | } 650 | -- Dynamo:- Lucas E.575. Cut-out:- Lucas "B". Cold. | 1. 11.4 | -- | } 585 | 600 | 2. 12.25 | -1.5 | } | 3. 12.2 | -2.5 | } | 4. 10.5 | -- | } 565 | -- Hot. | 1. 16.0 | -- | } 820 | 740 | 2. 14.5 | +2.1 | } | 3. 13.0 | -1.8 | } | 4. 12.0 | -- | } 660 | -- R.R. 235 A (100 T) (S.F. 846. 6-8-19) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2460. | ||