Abstract: A switching system for sequential connection of a plurality of loads to an alternating current supply comprises a computer for generating switch selection data in the form of serial bits along a single line to a distributor arrangement which decodes the selection data and provides control signals to switch devices which connect the loads to the supply. The distributor arrangement includes a circuit for inhibiting supply of the control signals to the respective switch devices unless the voltage of the supply phase connected by the device is substantially zero. Additionally the control signals are time-advanced with respect to the zero voltage conditions so that the switch devices can be placed in states in which they can connect a load before disconnection of a preceding load.

Abstract: A battery powered electric vehicle d.c. motor control includes a first potentiometer actuable by an accelerator pedal and a second potentiometer actuable by a brake pedal. The motor current is controlled in accordance with the signals at the sliders of these potentiometers and contactors determine the connection mode of the motor under the control of a comparator which is sensitive to the signal at the slider of the first potentiometer only. This causes braking mode to be selected except when the accelerator pedal is depressed. A resistor is connected in series with the second potentiometer to ensure that a minimum braking demand signal is always present, but means is provided for cancelling this minimum braking demand signal in certain vehicle operating conditions and further means is connected to the comparator for overridingly selecting motoring mode in these conditions.

Abstract: A fuel system includes a known hydromechanical governor fuel control, which has an electromechanical trim device. The trim device is controlled by a circuit which includes an error signal generating means for producing an error signal representing the difference between the desired and actual values of an engine parameter a proportional-plus-integral controller circuit, a trim datum signal generator and a differentiator which connects the generator to the integrator of the controller, so that in transient conditions the integrator output will ramp to a new value required for a new steady state condition.

Abstract: An i.c. engine fuel control system includes a closed loop roughness control, utilizing a roughness sensor circuit, an integrator which integrates the error between the roughness signal and a reference signal and modifies the fuel flow to the engine via a main fuel control with a variable frequency clock. During acceleration and deceleration the closed loop is interrupted by means of a circuit including two differentiators which are sensitive to throttle opening (speed demand) and actual speed respectively, and switches controlled by these differentiators.