The most direct answer: select your aluminum alloy tubular bus bar based on four core parameters — alloy grade, outer diameter and wall thickness, aluminum tubular busbar current rating, and the environmental conditions of your installation site. The purpose of this document is to detail the requirements of Northern Powergrid in relation to the tubular busbar systems and associated fittings detailed within this document. This document supersedes the following documents, all copies of which should be destroyed. Aluminium offers strong electrical conductivity at roughly half the weight of copper, with built-in corrosion resistance and full recyclability. There are added benefits from an electrical perspective. Insulation provides an inside and outside barrier to its installed environment.