IEC TR 61597-2021 PDF

Full title and description

IEC TR 61597:2021 — Overhead electrical conductors - Calculation methods for stranded bare conductors. This Technical Report provides practical calculation methods, conductor properties and worked examples for aluminium and aluminium-clad steel stranded bare conductors (covers current-carrying capacity, AC/DC resistance, mechanical properties and temperature effects).

Abstract

This second edition (2021) is a technical revision of IEC TR 61597:1995 and supplies straightforward, engineering-oriented calculation methods and indicative data for stranded bare conductors used on overhead lines. Topics include methods for calculating current-carrying capacity, alternating-current resistance (including guidance on hysteresis and eddy-current losses), inductive/capacitive reactances, thermal elongation and coefficients of linear expansion, creep and loss of strength of aluminium wires at elevated temperatures, plus practical examples and indicative calculation conditions.

General information

• Status: Current / Valid Technical Report.
• Publication date: 29 June 2021.
• Publisher: International Electrotechnical Commission (IEC).
• ICS / categories: 29.240.20 — Power transmission and distribution lines.
• Edition / version: Edition 2.0 (2021), Technical Report.
• Number of pages: 30 pages (official IEC publication details).

Key bibliographic details above are taken from the IEC publication record.

Scope

IEC TR 61597:2021 provides information relevant to conductors specified in IEC 61089 and to other aluminium and aluminium-steel conductors. The report supplies practical calculation methods and indicative data rather than exhaustive theoretical treatments. Clauses cover current-carrying capacity calculations (with a worked example), AC resistance and reactances (with added guidance on hysteresis and eddy-current losses), thermal elongation and coefficients of linear expansion for newer aluminium alloys and aluminium-clad steel, conductor creep, and reduction of strength of aluminium wires at high temperatures. Annexes provide a practical CCC example and indicative calculation conditions. This edition cancels and replaces the 1995 edition.

Key topics and requirements

• Calculation methods for current-carrying capacity (CCC) of stranded bare conductors, with a worked example.
• Formulas and guidance for alternating-current resistance including considerations of hysteresis and eddy-current losses in composite conductors.
• Inductive and capacitive reactance estimation for stranded conductors in overhead-line configurations.
• Thermal elongation data, coefficients of linear expansion for aluminium alloys and aluminium-clad steel series.
• Conductor creep behaviour and practical implications for long-term sag and tension.
• Temperature-related loss of mechanical strength for aluminium wires and recommended design considerations.
• Annexes with practical CCC example and indicative calculation conditions to aid engineering application.

These topics reflect the principal technical changes and additions introduced in the 2021 revision.

Typical use and users

Used by power transmission and distribution engineers, overhead-line designers, conductor and cable manufacturers, test laboratories, standards bodies and academic researchers who require practical calculation methods and design guidance for stranded bare aluminium and aluminium-clad steel conductors. The report is intended as a practical supplement to normative standards (for example IEC 61089) rather than as a prescriptive specification.

Related standards

Mainly related to IEC 61089 (conductors — round wire concentric-lay stranded conductors) and other IEC publications on overhead conductors and line design; the 2021 TR replaces IEC TR 61597:1995. Users implementing calculations should cross-check relevant normative standards (e.g., IEC 61089) and national line-design standards.

Keywords

Overhead conductors, stranded bare conductors, aluminium conductors, aluminium-clad steel, current-carrying capacity (CCC), AC resistance, eddy-current losses, hysteresis losses, thermal elongation, conductor creep, overhead lines, IEC TR 61597:2021.

FAQ

Q: What is this standard?

A: IEC TR 61597:2021 is an IEC Technical Report titled "Overhead electrical conductors - Calculation methods for stranded bare conductors" that provides practical calculation methods and indicative property data for aluminium and aluminium-clad steel stranded conductors.

Q: What does it cover?

A: It covers calculation methods for current-carrying capacity, AC resistance and reactances (with guidance on hysteresis and eddy-current losses), thermal elongation and expansion coefficients, conductor creep and loss of strength at high temperatures, plus annexes with a worked CCC example and indicative conditions for calculations.

Q: Who typically uses it?

A: Power transmission/distribution engineers, overhead-line designers, conductor manufacturers, testing laboratories and standards committees use this Technical Report as practical guidance alongside normative standards.

Q: Is it current or superseded?

A: The 2021 edition is the current IEC Technical Report and it cancels and replaces IEC TR 61597:1995. The IEC record lists the 2021 edition as the active/revised publication.

Q: Is it part of a series?

A: It is a Technical Report produced under IEC technical committee TC 7 (Overhead electrical conductors) and is intended to complement related IEC standards on conductors (notably IEC 61089) and other IEC publications addressing overhead-line design.

Q: What are the key keywords?

A: Overhead conductors; stranded bare conductors; aluminium conductor; aluminium-clad steel; current-carrying capacity; AC resistance; conductor creep; thermal elongation; IEC TR 61597:2021.