METHOD FOR TESTING OF CONTACT JOINT STATE IN ELECTRIC CIRCUITS Russian patent published in 2014 - IPC G01R31/00 

FIELD: electricity.

SUBSTANCE: invention is referred to the field of electric machine engineering and can be used for manufacture of process test systems related to operation of contact joints in electric circuits in industry and transport. The method lies in that current pulse with DC component is supplied to a deenergised contact joint, then current signals and voltage drop of this current at contact joint terminals are recorded, current and voltage curves are transformed into Fourier series, active and reactive resistance is determined for the contact joint for each harmonics of current and voltage. Harmonics related to the current source are subtracted from voltage drop spectrum. State of the contact joint is assessed against remaining harmonics of voltage spectrum by means of harmonic comparing with specific defects of the contact joint, active and reactive resistance values of harmonics are compared with the reference values for this type of the contact joint.

EFFECT: providing control for dynamics of development of contact joint deterioration process.