An electrical connection device for an electrical apparatus includes a connection pad and two attachment flanges arranged on either side of the connection pad. The attachment flanges and the connection pad include opposing cavities for delimiting four recesses capable of receiving at most four conductors. A pass-through clamping mechanism, formed by two lateral tie rods and a central rod, passes through the assembly constituted by superposition of the attachment flanges and the connection pad. The lateral tie rods include a support abutment arranged between the connection pad and one of the attachment flanges so that it is possible to differentiate the tightening, recess by recess, facilitating the placing of the conductors, the conductors being able to have different diameters.