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).
Blueprint of circuit diagrams for main and auxiliary contacts.
| Identifier | ExFiles\Box 149\3\ scan0036 | |
| Date | 27th February 1939 guessed | |
| COIL AUXILIARY CONTACTS MAIN CONTACTS MAKING MAIN CONTACTS BREAKING A 100Ω RESISTANCE ALWAYS FITTED B LOW RESISTANCE IN CIRCUIT WITH AUXILIARY POINTS THE LOWER AUXILIARY CONTACT POINT IS FIXED & THE SPRING OF THE UPPER CONTACT BLADE DOES NOT ALLOW THE MAIN CONTACTS TO OPEN UNTIL THE AUXILIARY CONTACTS ARE CLOSED, WHICH CONNECTS THE RESISTANCE 'B' IN PARALLEL WITH THE COIL. THIS LEAVES A LOW RESISTANCE CIRCUIT FOR THE INDUCED CURRENT. | ||