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).
Specification sheet for 600 Megohm Grade electric cable.
| Identifier | ExFiles\Box 168b\2\ img091 | |
| Date | 30th November 1922 | |
| ROLLS ROYCE LIMITED. MATERIAL Electric Cable. 600 Megohm Grade. SPECIFICATION NUMBER 253. Ferflex Braided. TYPE OF CORE Twin CORE SIZE 2 - 40/36 OUTSIDE DIAMETER .375 Maximum. CONDUCTOR High Conductivity Tinned Copper Wire DIELECTRIC One layer pure and two layers vulcanizing rubber. Both to be equal in quality to First Grade Plantation Rubber. The Vulcanizing Rubber shall contain at least 40% Pure Rubber. Mineral fillers only shall be used. Proportion by weight of sulphur shall not exceed 2.5%. The radial thickness of the pure rubber shall be at least .006 and the total thickness of the dielectric must be .035 minimum. PROTECTIVE COVERING Both cores to be taped. One coloured Red and the other White. Cores twisted together and wormed circular with cotton. Taped and protected overall with a Ferflex braid of 36 SWG. Tinned Copper Wire. | ||