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 results comparing leakage in Redmanol and Stabalite coil cases at various temperatures.
| Identifier | ExFiles\Box 39\3\ Scan266 | |
| Date | 16th September 1926 | |
| Contd. -4- EFC1/T16.9.26. cases, because it is quite clear from comparative results even now that there are variations from coil case to coil case, and variations according to the subsequent heat treatment of any individual coil case, also though it may not be realised, the leakage of these redmanol coil cases is even now many times more than the stabalite ones which have been replaced. The results of the tests are contained in the following tables and notes :- Results for coil cases:- Tin-foil electrodes were placed on the inside and outside of the coil cases which were raised in temperature by steps of 20°C to 100°C, readings being taken at each temperature. Results on seven Redmanol cases and on one standard stabalite case similarly tested for comparison are given, the figures being in micro-amperes. Coil case No. | Temperature °C. | 20 | 40 | 60 | 80 | 100 ----------------------------------------------------- 1 | 21 | 70 | 160 | 560 | 1620 2 | 7 | 70 | 350 | 1050 | 2950 3 | 14 | 42 | 148 | 577 | 2110 4 | 3.5 | 35 | 175 | 775 | 2320 5 | 0 | 3.5 | 126 | 740 | 1970 6 | 7 | 35 | 140 | 490 | 1200 7 | 14 | 100 | 316 | 985 | 2600 Stabalite. | 6 | 0 | 5 | 7 | 10 N.B. R.M.S. A.C. test voltage = 2400 Contd. | ||