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 mileage and electrical breakdown test results for various cable insulation types.
| Identifier | WestWitteringFiles\T\2July1929-December1929\ Scan197 | |
| Date | 1st December 1929 | |
| -5- EFC4/AD6.12.29 contd. "Samples of Gloverite and Super Glover were run over 10,000 miles on experimental Phantom I chassis 12-EX, and samples of Maconite and Helsby were run a second 10,000 miles test on the same chassis 12-EX, the wires being suitably sandwiched between battery and magneto ignition in each case. An examination of the cables at the end of these runs revealed the Gloverite to be in a very poor condition, the insulation having perished and cracked badly. The Super Glover cables with the exception of slight surface cracking appeared to be O.K. The Helsby cables had perished and cracked badly on three of the six cables whilst the Maconite, except for slight cracking at the surface on one or two of the cables, was in very good condition". (9) This consisted of a repetition of the electrical test referred to in (4) above, i.e. breakdown test in water after 24 hours immersion, and in relation to this, report WD.{Mr Wood/Mr Whitehead}92 reads as follows :- "Only one sample of Gloverite was in a suitable condition to test, and this broke down at 10,000 volts R.M.S. The Super Glover samples were better, one breaking down after 3 mins. at 18,600 volts R.M.S. whilst the other successfully withstood 19,000 volts R.M.S. for 15 mins. Two of the best samples each of the Helsby and Maconite | ||