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 for a 3 Core Electric Cable, 600 Megohm Grade.
| Identifier | ExFiles\Box 168b\2\ img093 | |
| Date | 30th November 1922 | |
| ROLLS ROYCE LIMITED. MATERIAL: Electric Cable. 600 Megohm Grade. SPECIFICATION NUMBER: 255. Ferflex Braided. TYPE OF CORE: 3 Core CORE SIZE: 2 - 90/36 1 - 70/36. OUTSIDE DIAMETER: .460" Maximum. CONDUCTOR: High Conductivity Tinned Copper Wire. DIELECTRIC: One layer of pure rubber and two layers of 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 to 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 radial thickness of the dielectric must be .035 minimum. PROTECTIVE COVERING: Each core taped 1 - 90/36 coloured Red, and the other White, the 70/36 coloured Black. Cores twisted together and wormed circular with cotton. Taped and protected overall with a Ferflex braid of 36 SWG. Tinned Copper Wire. | ||