A connector assembly (100,500) includes a plate (101,501) having a body (107,507) and one or more legs (108,109,110,508,509,510) extending distally from the body. The body can define an aperture (112,512). A flexible substrate (102,502) can electrically couple to the legs such that a portion (202,602) of the body extends distally from an edge (203,603) of the flexible substrate. A connector (103,503) is electrically coupled to the flexible substrate, with one or more circuit components (104,105,504,505) electrically coupled between the legs and the connector. The flexible substrate can define a perimeter (201,601) that is complementary in shape to an upper surface (122,522) of a busbar connector (106,506).