High-current tests are only as reliable as the currents delivered and the systems that measure them. IEC 62475:2026 supplies the definitions, parameter tolerances, and measuring-system requirements on which such tests rely. This page outlines the standard's scope, the equipment and current types it covers, and the compliance work it involves for testing engineers, procurement specialists, and quality managers.
Standard Information
IEC 62475:2026, titled "High-current test techniques - Definitions and requirements for test currents and measuring systems", is the current reference document for high-current test practice. The second edition cancels and replaces the first edition published in 2010 and constitutes a technical revision. Terms and definitions have been modified to adhere to IEC 60060-2:2025 and have been ascribed appropriate source references. - Designation: IEC 62475:2026
- Full title: High-current test techniques - Definitions and requirements for test currents and measuring systems
- Status: Current
- Publication date: 2026-07-30
- ICS classification: 19, 19.080
- Technical committee: TC 42 The status "Current" identifies this edition as the applicable text at the time of writing.
Scope and Application
The standard applies to high-current testing and measurements on both high-voltage and low-voltage equipment. It addresses three current categories. The first is steady-state and short-time direct current, as encountered in high-power DC testing. The second is steady-state and short-time alternating current, as encountered in high-power AC testing. The third is impulse current. In general, currents above 100 A are considered, although currents less than this can occur in tests. The document defines the terms used in high-current testing and sets the parameters and their tolerances. It describes methods to estimate the uncertainties of high-current measurements. It states the requirements applicable to a complete measuring system, and it describes methods for approving a measuring system and checking its components. It further describes the procedure by which the user shows that a measuring system meets the requirements, including limits set for uncertainty of measurement. A separate function concerns fault detection during, for example, lightning impulse testing. One technical change in this edition is relevant to laboratories: Clause B.4 of Annex B has been amended to give an example of uncertainty calculation for the use of an approved measuring system.
Products and Materials Covered
The ICS record places the document in section 19 (Testing), subclass 19.080, which groups electrical and electronic testing standards. Its subject is not a single product family. It applies wherever high-current tests are performed on high-voltage or low-voltage equipment, whatever the nature of the test current. Two object categories fall within its requirements. The first is the equipment under test: apparatus subjected to high-power AC or DC testing, or to impulse-current testing. The second is the measuring system itself, together with its components. The standard states requirements for a complete measuring system and describes how such systems are approved and checked. Current magnitude marks the practical boundary. Installations producing currents above 100 A form the primary field of application, with the understanding that individual tests can involve lower currents.
Testing and Compliance Considerations
Testing laboratories meet this type of document in two settings. The first is type testing and acceptance verification, where the behavior of equipment under high direct, alternating, or impulse currents must be characterized and documented. The second is the qualification of the measuring equipment itself, since approval of the measuring system and checking of its components belong to the standard's stated purpose. Compliance work centers on demonstrating that a measuring system meets the requirements, including the limits set for uncertainty of measurement. An accredited laboratory assembles the supporting evidence. Typical records include uncertainty estimates prepared with the methods described, results of component checks, and approval documentation. These records are retained within the laboratory's quality system, and routine checks confirm that an approved system continues to meet the assessed requirements. Retests or re-approval are commonly triggered by changes to the measuring chain, such as component replacement or modification, and by the review cycles fixed in quality procedures. Procurement specialists and quality managers can draw on the parameter and tolerance definitions when specifying high-current test requirements in contracts or purchase documents.
Related Standards and Series Context
The designation carries structural information. The prefix "IEC" identifies an International Standard published by the International Electrotechnical Commission. The number 62475 is the document's number in the IEC catalogue. The designation carries no part suffix, so IEC 62475 stands as a single, self-contained document rather than one part of a multipart series. The figure after the colon, 2026, gives the publication year of the edition in force. This is the second edition and constitutes a technical revision of the earlier text. The status "Current" indicates the applicable version; users should confirm status and obtain the official document through IEC sources rather than through this overview. Content responsibility rests with Technical Committee 42, the IEC body that maintains the document. In laboratory reports and specifications, the designation is normally cited in full — IEC 62475:2026 — so that the edition applied is unambiguous.
Frequently Asked Questions
Which products and materials does IEC 62475:2026 – High-current test techniques apply to?
IEC 62475:2026 – High-current test techniques applies to high-current test equipment and the products, components, and materials evaluated with it, including electrical apparatus subjected to large-magnitude current tests. The scope covers laboratories and manufacturers performing high-current verification, along with the conductors, connections, and assemblies used within such test circuits.
What does an IEC 62475:2026 – High-current test techniques report contain, and how is it used?
A report under IEC 62475:2026 – High-current test techniques documents the test setup, applied current parameters, observed results, and the compliance conclusion. Manufacturers, certification bodies, and purchasers use such reports to demonstrate that equipment meets the standard's requirements, supporting market access, design validation, and procurement decisions.
How do I submit equipment for IEC 62475:2026 – High-current test techniques evaluation, and what should I communicate?
Submission typically begins by contacting a testing laboratory and providing product specifications, ratings, and intended application details. Clearly communicate the scope of testing required under IEC 62475:2026 – High-current test techniques, any prior test data, sample availability, and target timelines, so the laboratory can prepare an accurate test plan.