Device and method to control a power source

An apparatus for providing a voltage reduction capability in a welding power source, said apparatus comprising:

• a tuned receiver circuit configured within said welding power source to receive an oscillating signal induced in a welding output current path within said welding power source and to generate a logical load condition signal therefrom;
• a voltage sensing circuit configured within said welding power source to detect a voltage between an electrode output terminal and a workpiece output terminal of said welding power source and to generate a logical output voltage condition signal;
• a voltage reduction device (VRD) switch in series with a main ON/OFF switch of said welding power source and a coil of an input power contact relay of said welding power source on an input power side of said welding power source;
• and
• a voltage reduction device (VRD) control logic circuit configured within said welding power source to open said VRD switch when said logical load condition signal indicates a no-load condition and said logical output voltage condition signal indicates a high output voltage condition.

A method of providing a voltage reduction capability in a welding power source, said method comprising:

• sensing an induced signal, within a welding power source, to generate a sensed signal being indicative of a load condition or a no-load condition between an electrode output terminal and a workpiece output terminal of said welding power source;
• detecting an output voltage, within said welding power source, being indicative of a low output voltage condition or a high output voltage condition across said electrode output terminal and said workpiece output terminal;
• and
• disabling an input power side of said welding power source, within said welding power source, by automatically opening a VRD switch on said input power side that is in series with a main ON/OFF switch of said welding power source and a coil of an input power contact relay of said welding power source, when said sensed signal is indicative of a no-load condition and said output voltage is indicative of a high output voltage condition.