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BC

Definition

BC is the industry abbreviation for bare copper, which refers to a copper conductor that has no coating or insulation.

Detailed Explanation

In commercial and industrial wiring, bare copper (BC) is valued for its excellent conductivity and flexibility. Unlike tinned or coated copper, BC has no surface treatment, making it suitable where oxidation is minimal or the conductor is protected by insulation or conduit. It is widely used as a grounding conductor, bonding wire, or as part of multi-conductor cable assemblies. Because it lacks insulation, BC is not intended for open-air current carrying unless used in a specified grounding path or approved cable design. Available in solid or stranded forms, BC remains a cost-effective choice for AV systems, fire alarms, building automation, and security wiring.

Abbreviation / Alternate Name

  • BC
  • Bare copper wire
  • Bare conductor

Regulatory Body or Governing Organization

Applications of bare copper are regulated by the NEC (National Electrical Code) and evaluated by UL (Underwriters Laboratories) and IEEE (Institute of Electrical and Electronics Engineers) for compliance and safety.

History

Copper has been used as a conductor since the late 19th century for its superior conductivity and durability. The abbreviation “BC” became standard in wire and cable specifications to distinguish bare copper from other types, such as tinned copper (TC). Over decades of evolving electrical codes, BC has remained a cornerstone in grounding and bonding practices.

Applications / Use Cases

  • Grounding conductors in commercial electrical systems
  • Drain wires in shielded cable constructions
  • Power-limited circuits, security wiring, and low-voltage control systems
  • Bonding grids and grounding electrode systems in industrial or data center environments

Related Terms

  • Conductor
  • Tinned Copper (TC)
  • Grounding
  • Solid Wire
  • Stranded Wire