Abstract: An electronic governor, particularly for a diesel engine has a summing amplifier receiving signals representing the output of the pumps supplying fuel to the engine, engine speed, and engine demand. The summing amplifier serves to produce an output for operating the pump in accordance with predetermined engine current characteristics. A second summing amplifier may be used to override the first summing amplifier to limit maximum fuel. Alternatively, the first summing amplifier may compare demanded fuel supply with actual fuel supply, in which case the second amplifier sets the maximum speed.

Abstract: A fuel system for an engine, particularly a compression-ignition engine, has a pump supplying fuel to the engine and a control member for determining the output of the pump, the control member being itself controlled by a control circuit receiving parameters one of which is measured by transducer means. The transducer means is designed so that if it fails, the fuel system fails safe. In another arrangement, in which failure of the transducer means results in an output which would increase fuel, then the failure is detected and action is taken.