two adjustable - stroke pumps are driven off a common drive shaft and supply fluid to respective consumers via respective control valves settable by the user of the system . each pump is provided with its own pressure regulator operative for regulating the output pressure of the respective pump by automatically adjusting the setting of the stroke - adjustment member of the pump . transducers generate first signals indicative of the settings of the stroke adjustment members and second signals indicative of the settings of the control valves . a control arrangement maintains the settings of the volume - adjustment members in correspondence with the settings of the control valves by automatically altering the operation of the pressure regulators in response to discrepancies between the settings indicated by the first and second signals . an anti - overload arrangement responds to overloading of the common drive machine for the pumps by altering the operation of the regulators in a way decreasing the stroke of one or both pumps . however , even during the anti - overload stroke decrease , the relative settings of the plurality of stroke - adjustment members are maintained in correspondence with the relative settings of the plurality of control valves .