An improved electrical system may be provided by electrically isolating horizontal power distribution bus bars of differing phases, disposed along a preconfigured isolated bus support molding, from one another by covering each bus bar with an electrically insulating molded assembly. The electrically insulating molded assembly has contours configured to cover a particular bus bar (with respect to another bus bar or live fastener), arranged within the constraints of the preconfigured isolated bus support molding in the electrical system (such as along the back of the isolated bus support, between the isolated bus support and a wall of the electrical system).