Patent ID: 7683290

Claim:
An apparatus to characterize a welding output circuit path with respect to an inductance of said welding output circuit path, said apparatus comprising a welding power source capable of: (a) regulating a welding output current applied to a welding output circuit path to a regulated output current value, or regulating a welding output voltage applied to said welding output circuit path to a regulated output voltage value; (b) measuring a value of a resultant welding output voltage at said regulated output current value, or measuring a value of a resultant welding output current at said regulated output voltage value; (c) calculating a resistance value of said welding output circuit path in response to said regulated output current value and said measured output voltage value, or in response to said regulated output voltage value and said measured output current value; (d) initiating a decaying of said welding output current from said regulated output current value or from said measured output current value; (e) sampling said decaying welding output current at a plurality of times from an initial current I o sampled at an initial time T o , to a final current I f sampled at a final time T f as said welding output current decays, forming a plurality of sample intervals; (f) calculating a dissipated energy within said welding output circuit path in response to each said sample interval of the welding output current between said initial current I o and said final current I f and in response to said resistance value; (g) calculating a total dissipated energy for said welding output circuit path in response to said calculated dissipated energies for each said sample of welding output current between said initial current I o and said final current I f ; and (h) calculating an inductance value of said welding output circuit path in response to said total dissipated energy, said initial current I o , and said final current I f .