Commercial and industrial distribution systems use various methods to conduct electrical energy. These methods often include heavy conductors run in trays or conduit.
Cable and conduit assemblies are costly and time consuming to install. Once installed, they are difficult to change. To eliminate these shortcomings, power is often distributed using enclosed bus bars. This is referred to as busway.

Busway is defined by the National Electrical Manufacturers Association (NEMA) as a prefabricated electrical distribution system consisting of bus bars in a protective enclosure, including straight lengths, fittings, devices, and accessories. Busway includes bus bars, an insulating and/or support
material, and a housing.
A major advantage of busway is the ease with which busway sections are connected. Electrical power can be supplied to any
area of a building by connecting standard lengths of busway. It
typically takes up to 35% fewer man-hours to install or change a
busway system than cable and conduit assemblies
types of busway installations:
- Horizontal Busway
- Vertical Busway