A switching circuit for an alternating current line allows the voltage or rrent coupled from the line to a load circuit to be controlled. Control may be in response to changes in voltage or current coupled as a feedback signal from the load to a switching circuit in the line for applying or terminating alternating current line voltages. In an alternative embodiment a switching circuit is initiated at the time alternating current voltages are applied to a load and after a predetermined time interval the switching circuit operates to disconnect and lock out the alternating current voltage.
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