مُحوّل نجمي-نجمي Yy Drehstromtransformator mit vier Anzapfungen, Three-phase transformer with four tappings (taps), connection: star-star Trasformatore trifase con quattro prese (oltre la presa principale) su un avvolgimento, collegamento stella-stella Transformateur étoile-étoile Transformator Yy Třífázový transformátor hvězda-hvězda (Y Y) Transformator Ster/Ster Author: The QElectroTech team License: see http://qelectrotech.org/wiki/doc/elements_license