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 an Electric Cable, 600 Megohm Grade.
| Identifier | ExFiles\Box 168b\2\ img090 | |
| Date | 30th November 1919 | |
| ROLLS ROYCE LIMITED MATERIAL: Electric Cable. 600 Megohm Grade. SPECIFICATION NUMBER: 252. TYPE OF CORE: Single. CORE SIZE: 84/25 OUTSIDE DIAMETER: .425 Maximum. CONDUCTOR: High Conductivity Tinned Copper Wire. DIELECTRIC: One layer pure rubber and two layers Vulcanizing Rubber. The rubber in each case shall be equal in quality to first Grade Plantation Rubber. Total thickness of dielectric not less than .050". The thickness of pure rubber must be at least .007". 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%. PROTECTIVE COVERING: Oil resisting varnished cambric tape applied spirally. Cotton braided and compounded black. Workshop finish. | ||