The invention relates to an assembly of a T-shaped connector (1) comprising a line input (4), a line output (5) and a measuring socket (2), wherein a measuring device (3), in particular an electrical voltage sensor, is arranged in the measuring socket (2), wherein the measuring device (3) comprises a coupling element (6) for connecting the measuring device (3) to the measuring socket (2), as well as a capacitor assembly with two electrodes (7, 8) located opposite one another, wherein the first electrode (7) is arranged on the coupling element (6) and wherein the second electrode (8) is arranged on an grounding element (9), wherein the measuring socket (2) has a receiving area (10) with a receiving area depth (10′) and wherein the measuring device (3) has an insertion area (11) with an insertion area length (11′), wherein the insertion area depth (10′) is smaller than or equal to the insertion area length (11′), and wherein the second electrode (8) extends into the insertion area (10) of the measuring socket (2).