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 temperatures of dynamo, ignition coil, and condenser units using fusible sentinels.
| Identifier | ExFiles\Box 52\3\ Scan124 | |
| Date | 4th September 1923 | |
| X4430 To R & E. {Mr Elliott - Chief Engineer} from EFC. {E. Fowler Clarke - Electrical Engineer} c. c. W.J. & FH. c. EY. c. EF. EFC {E. Fowler Clarke - Electrical Engineer} 1/T4.9.23. 14079 X4383 X4430 TEMPERATURES OF DYNAMO, IGNITION COIL AND CONDENSER FOUND BY MEANS OF TEMPERATURE INDICATING SENTINELS. We have arranged suitable temperature indicating sentinels of fusible metals in such a manner as to indicate very nearly the working temperatures of the above three units, and the indications of these sentinels to date are as follows :- DYNAMO. After melting a number of 68º and 73º sentinels on dynamos, we have found the maximum temperature to be in the neighbourhood of 88º. 82º sentinels have twice been melted on 4GII, twice on 6GII and once on 7GII, remaining unmelted on 2GII and 3GII. 87º sentinels are now being arranged for 4GII and 6GII. IGNITION COIL. 73º sentinels have melted on 3GII, 4GII, 6GII and 7GII and have been replaced by 77º sentinels, two of which have melted, one on 3GII (bracket position), and once on 4GII (engine position). CONDENSER. Of 73º sentinels fitted to condensers on 3GII, 4GII, 6GII and 7GII, one on 4GII has become melted, but only after considerable time. Sentinels have all been replaced by 65º, which so far as we know at the moment are all unmelted, even on 4GII. EFC. {E. Fowler Clarke - Electrical Engineer} | ||