Concentric-Lay-Stranded Aluminum-Alloy 6201-T81 Conductors

B399/B399M- 04 (Reapproved 2015): Standard Specification for Concentric-Lay-Stranded Aluminum-Alloy 6201-T81 Conductors

For electrical engineers and designers working on power transmission and distribution infrastructure, specifying reliable conductors is paramount. ASTM B399/B399M-04 (Reapproved 2015), the Standard Specification for Concentric-Lay-Stranded Aluminum-Alloy 6201-T81 Conductors, provides an essential framework for ensuring the quality and performance of a critical component in electrical systems. This authoritative standard offers a proven path to selecting and utilizing conductors that meet stringent industry demands.

What is B399/B399M- 04 (Reapproved 2015)?

This ASTM standard precisely defines the requirements for manufacturing concentric-lay-stranded conductors made from aluminum-alloy 6201-T81 wires. Originating from the need for standardized, high-strength aluminum conductors, its primary purpose is to ensure these conductors possess the necessary electrical and mechanical properties for reliable use in various electrical applications.

Scope & Purpose

The scope of B399/B399M-04 (Reapproved 2015) encompasses the material composition, construction methods, and performance criteria for concentric-lay-stranded aluminum-alloy 6201-T81 conductors. It specifically covers conductors intended for electrical purposes, including those classified for bare overhead lines (Class AA) and those designed for eventual covering with insulating materials (Class A). The standard does not cover the insulation or jacketing materials themselves, nor does it specify installation procedures.

Who Must Comply?

• • Primary audience: Electrical Engineers, Materials Engineers, Quality Control Inspectors, Procurement Specialists, and Project Managers involved in electrical infrastructure projects.
• • Industries affected: Electrical Utilities, Power Transmission and Distribution, Telecommunications, Renewable Energy, and Electrical Equipment Manufacturing.
• • Compliance nature: Voluntary, but widely adopted and often mandated by project specifications and utility standards.
• • Enforcement: Typically enforced through project specifications, contractual agreements, and quality assurance programs during manufacturing and installation.

Key Requirements Overview

The standard requires that conductors be constructed from aluminum-alloy 6201-T81 wires conforming to specific material properties. Professionals must ensure the concentric-lay stranding adheres to defined patterns and lay lengths, with specific requirements for the central core and outer layers. Key provisions include detailed tables outlining conductor sizes, wire counts, diameters, and electrical resistance values at 20°C. The standard also specifies permissible types of joints in the constituent wires and defines criteria for conductor classification based on intended use.

Related Standards & References

This standard works in conjunction with ASTM B398/B398M, which specifies the requirements for the aluminum-alloy 6201-T81 wire itself. ASTM B354 provides essential terminology for uninsulated metallic electrical conductors, ensuring a common understanding of terms used within B399/B399M. Additionally, ANSI H35.1/H35.1[M] standards are referenced for alloy and temper designations, ensuring consistency in material identification.