Busway systems (referred to as busways) consist of a metal casing (made of steel or aluminum plates), conductive bars, insulating materials, and related accessories to form a busbar system. They can be manufactured into a plug-in type busway with junction boxes installed at regular intervals, or into a power supply type busway without junction boxes in the middle. In the power supply systems of high-rise buildings, power and lighting circuits are often separated, and busways are installed vertically along the walls in one or more runs within the electrical shaft as the main power supply lines.
A busway system, generally used for a single trip, consists of items such as the starting busway, through busways (with and without sockets), L-shaped vertical (horizontal) elbows, Z-shaped vertical (horizontal) offsets, T-shaped vertical (horizontal) tees, X-shaped vertical (horizontal) wyes, variable capacity busways, expansion busways, relevant accessories, and fastening devices.
Busbars can be divided into three types according to insulation methods: air-insulated busbars, dense-insulated busbars, and high-strength busbars.
High-strength enclosed busway (CFW). Its manufacturing process is not restricted by sheet materials; the housing is designed in a tile groove shape, enhancing the mechanical strength of the busbars. The horizontal sections of the busbars can be produced up to 13 meters in length. Due to the tile groove shape of the housing, the busbars are intentionally separated and fixed at the groove positions, with a spacing of 18mm between them, ensuring good ventilation between the busbars. This significantly improves the moisture-proof and heat dissipation functions of the busway, making it particularly suitable for southern climates. The presence of gaps between the wires reduces the temperature rise of the conductors, thereby increasing the overload capacity and reducing magnetic oscillation noise. However, it generates much higher stray currents and inductive reactance compared to dense busways, so its conductor cross-sectional area is larger when compared to the same specifications of insulated busbars.