A double-contact control unit for electric plants, which is adapted to be anchored to a fixed or movable support element of an electric plant, comprises an insulating support (4) having a longitudinal axis (L) and a predetermined axial length (1), two pairs of fixed contacts (5, 5'; 6, 6') mounted to the support (4) in longitudinally offset positions and adapted to be connected to corresponding electric circuits associated with the plant to cooperate with respective pairs of movable contacts (13, 13'; 14, 14') for opening/closing the electric circuits, each of the fixed contacts (5, 5'; 6, 6') being associated with a respective electrical connection terminal (7, 7'; 8, 8'). The terminals (7, 7'; 8, 8') of each pair of fixed contacts (5, 5'; 6, 6') are located in symmetric positions with respect to the longitudinal axis (L), at distances and inclination angles (α) differing from those of the terminals (7, 7'; 8, 8') of the other pair of fixed contacts (5, 5'; 6, 6') and at least partially transversely aligned therewith to reduce the longitudinal offset of the pairs of fixed contacts (5, 5'; 6, 6') and the axial length (1) of the support (4).