Abstract: The present invention relates to a current and/or voltage transformer comprising at least one primary circuit P and one secondary circuit S. The transformer according to the invention comprises m elementary windings each having Ni turns, m and Ni being integer numbers, and i lying between l and a predetermined integer number n, said groups of elementary windings being capable of being associated in series and/or in parallel in such a way as to produce a particular configuration from among a plurality of distinct configurations of primary circuits P and of secondary circuits S each of said configurations corresponding to previously fixed electrical and magnetic parameters.