Stranded Copper Wire – Classification, Standards, and Technical Applications

Stranded copper wire is a specialized electrical conductor composed of multiple fine strands of refined copper twisted or braided together according to specific geometric configurations. This structure optimizes flexibility, electrical performance, and resistance to mechanical stress. Such conductors are widely used across industrial, residential, and electronic–telecommunication systems where transmission stability and long-term operational durability are required.

Depending on construction and final form, stranded copper wires are typically categorized into two major groups: concentric stranded wire and braided wire. Each type exhibits distinctive mechanical–electrical properties and adheres to its respective international standards for quality assurance.

DULICO currently supplies internationally certified copper wire in coil form, serving wire manufacturers, electrical equipment producers, and grounding system integrators both domestically and abroad.

1. Concentric Stranded Copper Wire

This type consists of multiple small-diameter copper strands twisted concentrically around a central wire, forming a uniform circular cross-section. It offers excellent conductivity, flexibility during installation, and superior electrothermal performance—making it a preferred choice for both industrial and household applications.

Applicable Standards:

• JIS C 3406: Tinned Soft Copper Stranded Wire
• JIS C 3407: Bare Soft Copper Stranded Wire
• IEC 60228: Class 2 / 5 / 6 (based on required flexibility and application)
• ASTM B8: Concentric-Lay-Stranded Copper Conductors

Typical Applications:

• Interconnecting conductors between components in electrical switchboards
• Flexible jumpers with terminal lugs for safe and convenient handling
• Neutral and grounding conductors in industrial and residential power systems
• Flexible conductors for UPS, inverter, and DC power systems

2. Braided Copper Wire

Unlike the concentric type, braided copper wire consists of interwoven copper strands forming a flat or tubular mesh structure. This geometry enhances vibration absorption, tensile strength, and mechanical load distribution, making it suitable for harsh or dynamic operating environments.

Applicable Standards:

• ASTM B173: Flat and Rope-Lay Braided Copper Conductors
• MIL-C-7078: Military Specification for Copper Wire Braid
• EN 13602: Copper and Copper Alloy Wire for Electrical Purposes

Technical Applications:

• Flexible grounding straps for industrial equipment, data centers, and substations
• Flexible busbars for transformers, switchgear, and heavy-current connections
• Vibration and thermal expansion connectors for robotic or moving assemblies
• EMI/RFI shielding for sensitive signal circuits and precision instrumentation

DULICO – Trusted Supplier of Stranded Copper Wire for Technical and Industrial Applications

DULICO provides a wide range of high-quality stranded copper wire products that meet international standards and fulfill various engineering and manufacturing requirements in the electrical, mechanical, and electronic industries.

Product Specifications:

• Electrical conductivity ≥ 99.95% IACS
• Supplied in coil form, available in annealed (soft) or hard-drawn states
• Wide range of diameters and constructions (from Ø0.05 mm upwards)
• Available in tinned or bare finish to enhance oxidation resistance and contact stability
• Strictly tested for conductivity, resistance, elongation, and surface purity

Our customers include electrical system installers, power equipment manufacturers, soft jumper producers, electromechanical component makers, and other enterprises utilizing copper wire as a key material in their production processes.

With over 30 years of expertise in copper and non-ferrous materials, DULICO is proud to be a reliable supply partner for high-quality copper strip and wire products in Vietnam’s industrial and manufacturing sectors.