Abstract: A control system for ohmic loads, particularly signal lamps of a traffic regulating system in response to periodic test pulses supplied under normal operating conditions of the ohmic loads in which an evaluation relay having an inherent delay and including an actuating winding is adapted to be energized by the discharge of a capacitor, the actuating winding forming a part of a series circuit including such capacitor and a diode with said capacitor being adapted to be charged from a power supply which forms a part of a second series circuit which also includes such capacitor as well as a further diode, and transistors for controlling the respective series circuits in response to said periodic test pulses, with the duration of the charge period of such capacitor being less than the inherent delay of said relay.