Relay circuit

摘要

A relay circuit contains a relay having at least one switching contact and a magnetic coil operating the switching contact, the current supply for the magnetic coil being supplied by a current supply circuit. In order that the current supply circuit can operate over a wide operating voltage range and is suitable for its function without a transformer and without any deterioration of the efficiency, a switched-mode power supply, having two outputs to which a filter capacitor is connected, is provided in the current supply circuit. The inductance of the switched-mode power supply is formed by the magnetic coil of the relay which, together with a freewheeling diode connected in series with it, is connected in parallel with the filter capacitor so that the relay is triggered or tripped as a function of the current consumption at the outputs of the switched-mode power supply, depending on whether the current consumption is above or below the triggering value. <IMAGE>