FIELD: electricity.
SUBSTANCE: invention is attributed to three-phase electric circuit diagnostics. Essence: the first indicator value is determined in each of three phases on the basis of relation between phase current value in measured phase and current negative component and relation between maximum of all phases and earthed phase circuit impedance. The second indicator value is determined in each of three phases on the basis of relation between phase currents maximum in all phases and phase current in measured phase and relation between maximum of first indicator values of all phases and first indicator in the measured phase. Faulty phase is determined if the second indicator value in this phase is lower than preset threshold value.
EFFECT: providing minimum of adjustments, independence from load variations, earthing conditions and current constant component variations.
14 cl, 2 dwg
