Manufactured Wiring Systems (MWS)

Known by names such as prefab wiring, prebuilt wiring and modular wiring, manufactured wiring systems (MWSs) have been in existence for about 25 years.  Although MWSs are recognized as a serious alternative to conventional wiring methods, the debate between the traditional pipe-and-wire approach to electrical installations and MWSs goes on.

National Fire Protection Association (NFPA) 70 – National Electrical Code (NEC) ARTICLE 604 — MANUFACTURED WIRING SYSTEMS

604.2 Definition.

“Manufactured Wiring System. A system containing component parts that are assembled in the process of manufacture and cannot be inspected at the building site without damage or destruction to the assembly and used for the connection of luminaires, utilization equipment, continuous plug-in type
busways, and other devices.”