Busway (also known as busway槽) is a busbar system consisting of a protective shell made of metal plates (steel or aluminum), conductive bars, insulating materials, and relevant accessories. It can be made into a plug-in type busway with junction boxes 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 separately installed. The busway serves as the main power line and is vertically mounted on the wall inside the electrical shaft one or more times.
A busway typically consists of components such as the starting busway, straight-through busway (available with and without sockets), L-shaped vertical (horizontal) bend bus, Z-shaped vertical (horizontal) offset bus, T-shaped vertical (horizontal) tee bus, X-shaped vertical (horizontal) cross bus, variable capacity busway, expansion busway, related accessories, and fastening devices.
Busbars can be categorized into three types according to their 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, with the housing designed in a corrugated form to enhance the mechanical strength of the busbars. The horizontal sections of the busbars can be produced up to 13 meters in length. Due to the corrugated housing design, 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 enhancing overload capacity and reducing magnetic oscillation noise. However, it generates much higher stray currents and inductive reactance compared to dense busways, so when compared with the same specifications, its conductor cross-section is larger than that of dense insulated busbars.