Busway is an economical, modern method of distributing electricity within a building. It is similar to the tracks that an electric model train runs upon, both in look and in function.
Train track sections can be snapped together to form a number of different paths for the train to follow. Likewise, sections of busway can be connected together in nearly any configuration to get power to wherever it is needed. Because of its versatility, busway is often less expensive to install. This is particularly true in an application where load locations are likely to change.
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.
busway components
- Housing The non-ventilated enclosure that prohibits the entry of dirt and moisture via a rugged two-piece aluminum housing.
- Insulation – Phase and neutral bars are insulated with an epoxy powder with excellent dielectric strength that is flame retardant and resists impacts better than other Class B insulations.
- Conductors – The metal phase and neutral bars (bus bars) that are the equivalent to electrical wire and can be either copper or aluminum.
Low Voltage and Medium Voltage Busway
- Busway is available in either low or medium voltages. Application determines the type needed
- Low Voltage Busway
- 600 volts and below 225
- 5,000 amp
- Utilizes an epoxy coated, sandwich system design
- Medium Voltage Busway
- 600 volts — 38,000 volts
- 1,200 — 5,000 amps
- Referred to as Non-Segregated Phase Bus Duct
- An assembly of epoxy coated bus conductors, confined within a metal enclosure without barriers between the phases
Busway vs. Cable
below benefits of using busway over traditional cable :
- Safe and Versatile
- Meets UL, NEMA, and CSA and is seismically qualified.
- Conductors are enclosed in a non-ventilated housing which provides highest short circuit ratings in the industry today.
- All bus plugs are polarized to prevent improper installation and plug-in outlets are rated for finger safety.
- Reusable, Expandable, Flexible
- You can relocate existing busway and add new runs to expand to new areas. Plus, it is easy to tap off power for manufacturing equipment and bench hand tools.
- Lower Installed Cost
- The savings in labor and installation time can generate a total installed cost reduction of 40% or more compared to cable and conduit.
- Compact Size
- The cross-sectional area is compact. It occupies less space than multiple conduits and makes it easier to coordinate runs with other trades such as heating, ventilation and plumbing.