Arrangement with at least one current transformer for the determination of the overloading of a current transformer possessing at least two windings

摘要

The arrangement contains a detector (5a; 5b; 8), a display device (9) and a registration device (10). It serves to determine and display saturation phenomena in at least one magnetic core (2a, 3b) of the current transformers (1) and to register the duration of the saturation phenomena. Two approximately identical magnetic cores (2a, 2b) of the current transformer (1) both have a common first and second winding (3; 4) and each have an approximately identical third winding (5a, 5b). The detector (5a; 5b; 8) consists of an auxiliary AC voltage source (8) and the two third windings (5a, 5b), which are connected in series so that an auxiliary AC current (I3) flowing through them in the two magnetic cores (2a, 2b ) generates magnetic fluxes of opposite polarity but the same amount, so that the alternating voltages induced by the magnetic fluxes in the other windings (3, 4) cancel each other out.