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).
Extract from the Marmon Car Instruction Book detailing the function of the electrical system's circuit breaker.
| Identifier | Morton\M1.7\ img004 | |
| Date | 3rd December 1921 guessed | |
| X3540 Electrical System. Extract from Marmon Car Instruction Book. ----- CIRCUIT BREAKER. ----- The circuit breaker mounted under the cowl takes the place of fuses. Two circuit breakers are used, both being carried in the same housing. These circuit breakers act as protective devices, preventing damage to the wiring and equipment by preventing an excessive flow of current in case of grounds or short circuits in the wiring or apparatus. The normal flow of current through the lighting circuits does not in any way affect the circuit breaker, but in the event of an abnormally heavy current such as would be caused by a ground in any of the lighting circuits, the circuit breaker will operate, interrupting the circuit intermittently, causing a vibrating sound. This vibration will continue until the ground is removed. One of the circuit breakers - the one in series with the horn, - tonneau light and trouble light, is a lockout circuit breaker. In case of a ground in these circuits the heavy flow of current will cause the contacts to open and they will be held open until the ground is removed and all the load is taken off the circuit. ---------o0o--------- | ||