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).
Production test table for a combined main and auxiliary switch unit.
| Identifier | ExFiles\Box 64\4\ scan0237 | |
| Date | 9th April 1929 | |
| X7655 PRODUCTION TEST TABLE of S.S. COMBINED MAIN SWITCH AND AUXILIARY SWITCH UNIT. II. MAIN SWITCH UNIT. Date. | Unit Number. | (1) Gap remarks. | (2) Amperes (7.5 to 8.5) | (3) Amperes + 7.0 | (4) Copper contact pressure > 7.5 Amperes. | Remarks. 9-4-29 | D | OK | 8.0 | 5.1 | 6.5 | OK. 10.1.29 | ||