Yes, 311.12 of the National Electrical Code (NEC) does apply to overhead ACSR (Aluminum Conductor Steel Reinforced) cables.Here's why: 311.12 Applicability

NEC 311.12 covers the marking requirements for conductors, specifically those intended for use in a raceway or cable. While ACSR is often used overhead and not in a raceway, the marking requirements are intended to provide essential information about the conductor regardless of its application.

Conductor Definition

The NEC defines a conductor as "A material, usually metal, having the property of conducting electrical current." ACSR cables are specifically designed to conduct electrical current and fit this definition.

Identification is Key

The markings required by 311.12 are important for proper identification of the conductor's size, type, voltage rating, and manufacturer. This is crucial for safety during installation, maintenance, and troubleshooting, regardless of whether the conductor is in a raceway, cable assembly, or used overhead.

What Markings are required



AWG Size

The AWG size of the Aluminum conductor (e.g. 4/0 AWG)

Type Letter Designation

(e.g. XHHW-2, THHN, etc.)

Voltage Rating

(e.g. 600V)

Manufacturer



UL Listing

UL listing is required.

Important Considerations and Clarifications



Specific Installation Requirements

While 311.12 applies to the marking of ACSR conductors, it's crucial to understand that other sections of the NEC will govern the installation of overhead conductors. This includes clearances, ampacity ratings, support requirements, and grounding. Specific sections like Article 225 (Outside Branch Circuits and Feeders) and Article 399 (Outside Overhead Conductors Over 1000 Volts, Nominal) are relevant for overhead installations.

Manufacturer's Specifications

Always consult the manufacturer's data sheet and installation instructions for the specific ACSR cable being used. These will provide crucial information on proper installation, tensioning, and handling, in addition to confirming that the cable meets applicable standards.

In summary: 311.12 applies to the marking of ACSR conductors, ensuring they are properly identified. However, remember that the NEC contains many other rules governing the safe and proper installation of overhead conductors. Always consult the full NEC and the manufacturer's specifications for complete compliance. Flag for review