ČSN EN IEC 62561-2 ed. 3: conductors and earth electrodes

ČSN EN IEC 62561-2 ed. 3 (classification code 35 7605) was approved on 1 October 2026 and published in October 2026. Its publication was announced by the Úřad pro technickou normalizaci, metrologii a státní zkušebnictví in Věstník ÚNMZ No. 10/2026, published on 8 October 2026. It is the Czech version of the European standard EN IEC 62561-2:2025, which adopts IEC 62561-2:2025. According to the standard’s catalogue record, it takes effect on 1 November 2026.

The standard covers requirements and tests for metallic conductors used in air-termination and down-conductor systems, as well as metallic earth electrodes used in earth-termination systems.

What the public notices confirm

The dates are stated in Věstník ÚNMZ and the public preview of the standard on the ČAS website:

The withdrawal date of the previous edition is also stated in the overview of changes to ČSN standards for October 2026.

The preview reproduces the following overview of significant technical changes from IEC:

• additional definitions of new conductor types;
• the salt mist test updated in accordance with IEC 60068-2-52:2017;
• the sulfur dioxide test in a humid atmosphere updated in accordance with ISO 22479:2019;
• a new normative Annex H on testing material, configuration and cross-sectional area;
• a new normative Annex I on the applicability of previous tests;
• the introduction of an earth grid.

The preview does not provide specific values or dimensions, so it cannot be used to infer a change to any particular conductor dimension or material.

Because both editions remain valid concurrently until 30 November 2028, the documentation should state which edition the designer used to specify the components and which edition the contractor used to select and document them.

When not to attempt it yourself and what we will do

Seek professional assessment before work begins, particularly when:

• the roof, air-termination system, down conductors or rooftop technology are being altered;
• work affects an earth electrode that will be buried, covered or encased once completed;
• the documentation does not specify the route, material or component dimensions, or does not match what has actually been installed on the building.

As part of its lightning protection and earthing inspections, SOHE can follow up in three steps:

1. we compare the available documentation with the actual condition of the installation;
2. we identify missing documents and define the scope of the necessary check or inspection;
3. once the work is complete, we review the handover documents and carry out the agreed inspection.

We will confirm the scope, price and schedule in advance for the specific property.

What to clarify for an ongoing project

The client should obtain written confirmation of:

• which edition was used for the design;
• which edition the contractor is using to select conductors, earth electrodes and related components;
• whether the change of edition affects products or documentation already ordered;
• who will assess any discrepancy between the design and the actual installation;
• which documents will be handed over before the earth electrodes are covered and during final acceptance.

A general statement such as “installed in accordance with applicable standards” will not subsequently make it possible to determine which of the two valid editions was used for the design and installation.

What to require during acceptance

The documentation should make it possible to determine what was actually installed, where concealed parts are routed and how the installation differs from the design. The edition of the standard should be consistent in both the design and handover documentation.

Component identification

Labels such as “lightning conductor wire” or “earthing strip” are insufficient for later identification. The documentation should make it possible to determine at least the manufacturer, product type, material and dimensions of the component used.

For products tested under the earlier edition, a reference to Annex I, which addresses the applicability of previous tests, is useful.

As-built documentation

Any change to a down-conductor route, the position of a test joint or another component should be recorded in the as-built documentation, rather than communicated only verbally by the installer.

Concealed earth electrodes

Before an earth electrode is buried or covered, request the following:

• photographs of its route and connections;
• a drawing of its route;
• its position relative to fixed and subsequently identifiable points on the building;
• identification of the components used;
• a record of any deviations from the design.

Documents for the inspection technician

Provide the inspection technician with the design, as-built documentation, component documentation and change records, ideally before the earth electrodes are covered.

What to do with an existing lightning protection system

For an installation already in service, do not begin by replacing all conductors and earth electrodes solely because a new edition of the standard has been published. First, gather:

• the original design and any available as-built documentation;
• the latest inspection report;
• repair records;
• information about roof refurbishment and the installation of photovoltaic panels, antennas or other technology;
• details of any work affecting the foundations, surrounding ground or earthing system.

How to compare quotations

The phrase “in accordance with the new standard” does not explain what the quotation includes. Compare:

• design preparation and any necessary design updates;
• the supplied conductors, earth electrodes and other components;
• installation and related building work;
• as-built documentation;
• photographs and drawings of concealed parts;
• the initial inspection or another agreed inspection;
• rectification of identified defects.

The price is determined not by the edition number, but by the scope of the installation, roof access, the condition of the earthing system and the available documentation.

Brief answer

ČSN EN IEC 62561-2 ed. 3 covers requirements and tests for metallic conductors and earth electrodes used in lightning protection systems. It was approved on 1 October 2026 and takes effect on 1 November 2026; the previous edition 2 may be used concurrently until 30 November 2028. For a new or ongoing project, have the applicable edition specified, the installed components identified and the earth electrodes documented before they are covered.

Frequently asked questions

Does edition 3 mean that an old lightning protection system must be replaced?

The publication of a new edition does not in itself demonstrate a need for replacement. The documentation, the actual condition of the installation and any changes made to the building, roof or earthing system must be assessed first.

When does ČSN EN IEC 62561-2 ed. 3 take effect?

The catalogue record states that it was approved on 1 October 2026 and takes effect on 1 November 2026.

When will edition 2 be withdrawn?

Věstník ÚNMZ No. 10/2026 states that ČSN EN IEC 62561-2 ed. 2 will be withdrawn with effect from 30 November 2028. According to the national foreword, it may be used concurrently with edition 3 until then.

What should the order specify?

The order should specify the applicable edition of the standard, the scope of supply, responsibility for recording changes and the list of documents to be handed over before the earth electrodes are covered and after completion.

Sources used for this article

• Lightning protection system inspections – a SOHE service.
• New lightning protection standard ČSN EN IEC 62305 – background on changes to the main series of lightning protection standards.
• Lightning protection documentation for an older building – what to do when the design or as-built documentation is missing.
• Lightning protection inspection for an industrial hall – documentation and operational considerations for larger properties.
• Věstník ÚNMZ No. 10/2026 – notice of the publication of the new edition and withdrawal of edition 2 on 30 November 2028.
• Preview of ČSN EN IEC 62561-2 ed. 3 (ČAS) – national foreword, concurrent use and overview of changes.
• Catalogue record for ČSN EN IEC 62561-2 ed. 3 – approval and effective dates.
• Overview of changes to ČSN standards for October 2026 – information about the withdrawal of the previous edition.

This article is for information only and does not constitute legal advice. The specific arrangements for design, installation, checks and inspection must reflect actual operating conditions, the manufacturer’s documentation, the environment of use and the risk assessment.

Do you need an assessment of the documentation, the condition of the installation or completed installation work? We provide lightning protection system inspections for businesses, building owners and homeowners’ associations; we will confirm the price and schedule in advance based on the specific scope. Send us a no-obligation enquiry or email info@sohe.cz.