ASTM B856 specifies requirements for round wire concentric-lay-stranded aluminum conductors, steel-supported (ACSS) used exclusively as overhead electrical conductors.
Testing Protocol:
Mechanical and electrical properties of aluminum wires are verified after stranding.
Electrical Validation:
Post-stranding electrical resistivity must meet specified minimum requirements.
Unit Systems:
Values in inch-pound or SI units are separate standards (combining systems causes noncompliance).
SI units govern density, resistivity, and temperature.
Conductor Sizing:
Sizes designated by AWG/kcmil: SI requirements converted from inch-pound values.
Sizes designated by SI units only: Requirements directly stated/derived in SI units.
Compliance Basis:
Developed per WTO Technical Barriers to Trade (TBT) Committee principles.
Ensures reliable performance of ACSS conductors by:
Validating mechanical strength post-stranding
Guaranteeing electrical resistivity thresholds
Maintaining standardized dimensions
Exclusively applied for overhead electrical conductors in power transmission infrastructure.
