One system of the present application includes an electronic assembly with a heat dissipating device, printed wiring board with electronic circuitry, bus bar, insulative grommet, and fastener. The board defines a bus with an interconnection pad and a board opening. The bus bar connects with the interconnection pad and defines a bar opening with a beveled shoulder portion that align with the board opening to define a passage to a fastening site of the heat dissipating device. The grommet defines a distal end portion opposite a proximal end portion shaped with a flange. The distal end portion is inserted into the passage with the flange abutting the beveled shoulder portion. The fastener extends through the grommet to provide a mechanical connection of the board and bar to the site and maintain thermal coupling between the board and device while the grommet electrically insulates the fastener from the bar.