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).
Extract detailing how early experimental auto switches prevent dynamos from overheating.
| Identifier | ExFiles\Box 59\1\ Scan172 | |
| Date | 10th November 1927 | |
| X4008 Extract from EFCl/T10.11.27. (X.8671). The use of these sentinels (97°C) on the machines which have been fitted with auto switch charge reducers have shown that these early experimental auto switches prevent the dynamo from attaining such a high temperature. | ||