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 special ballast resistance unit, detailing wire type, length and resistance value.
| Identifier | ExFiles\Box 168a\5\ img025 | |
| Date | 6th November 1928 | |
| x7720 6.11.28. RE SPECIAL BALLAST RESISTANCE 1 1/4 INSTEAD OF DOUBLE VALUE. Upon measurement in the lab. we find that using 32 S.W.G. nickel wire 33.5" would be required. This has been notified to RD. EFC/HEW. Resistance at 18°C of the above unit = 1.35 ohms. | ||