Busbar for holding a contact wire, the busbar being arranged in a metal profile extending along a longitudinal axis and having a section comprising: - a base, extending in a median plane and arranged along the longitudinal axis, - two holding arms, each comprising: • a main portion that extends from the base, so that the two main portions are facing each other on either side of a longitudinal plane that is orthogonal to the median plane and parallel to the longitudinal axis, • a clamping portion, that comprises a first extremity, linked to the main portion, and a second extremity, opposite to the first extremity and forming a clamping tip configured to cooperate with the contact wire, wherein the two clamping portions extend toward the longitudinal plane and are configured to clamp onto the contact wire, wherein the two holding arms delimit an inner volume of the busbar, wherein each clamping portion also comprises a protective wall, which is arranged between its first extremity and the clamping tip, which extends within the inner volume and which is configured to prevent water condensing on the busbar within the inner volume to flow by gravity to the clamping tips, characterized in that: - the two protective walls include an upper wall and a lower wall, the upper wall being closer to the base than the lower wall, - the upper wall and the lower wall overlap each other along a direction orthogonal to the median plane, and delimit a volume configured to be filled with a paste, such as grease. - a base, extending in a median plane and arranged along the longitudinal axis, - two holding arms, each comprising: • a main portion that extends from the base, so that the two main portions are facing each other on either side of a longitudinal plane that is orthogonal to the median plane and parallel to the longitudinal axis, • a clamping portion, that comprises a first extremity, linked to the main portion, and a second extremity, opposite to the first extremity and forming a clamping tip configured to cooperate with the contact wire, • a main portion that extends from the base, so that the two main portions are facing each other on either side of a longitudinal plane that is orthogonal to the median plane and parallel to the longitudinal axis, • a clamping portion, that comprises a first extremity, linked to the main portion, and a second extremity, opposite to the first extremity and forming a clamping tip configured to cooperate with the contact wire, wherein the two clamping portions extend toward the longitudinal plane and are configured to clamp onto the contact wire, wherein the two holding arms delimit an inner volume of the busbar, wherein each clamping portion also comprises a protective wall, which is arranged between its first extremity and the clamping tip, which extends within the inner volume and which is configured to prevent water condensing on the busbar within the inner volume to flow by gravity to the clamping tips, characterized in that: - the two protective walls include an upper wall and a lower wall, the upper wall being closer to the base than the lower wall, - the upper wall and the lower wall overlap each other along a direction orthogonal to the median plane, and delimit a volume configured to be filled with a paste, such as grease. - the two protective walls include an upper wall and a lower wall, the upper wall being closer to the base than the lower wall, - the upper wall and the lower wall overlap each other along a direction orthogonal to the median plane, and delimit a volume configured to be filled with a paste, such as grease.