IEC 62561-3:2023

Overview

IEC 62561-3:2023 - "Lightning protection system components (LPSC) - Part 3: Requirements for isolating spark gaps (ISGs)" - is the third edition international standard that specifies requirements and test procedures for isolating spark gaps (ISGs) used in lightning protection systems (LPS). This 2023 edition cancels and replaces IEC 62561-3:2017 and introduces technical revisions including alignment with the latest ISO 22479 for humid sulphurous atmosphere treatment and a new normative Annex D on applicability of previous tests.

ISGs provide an indirect bonding method where a direct electrical bond is not permissible for functional reasons. The standard is intended for designers, manufacturers, test laboratories, installers and certifiers working with lightning protection components.

Key Topics and Requirements

• Scope and classification
  • Defines ISG use-cases and classification according to lightning-current capability and installation location.
• Environmental requirements and tests
  • Corrosion resistance (salt mist, humid sulphurous atmosphere per ISO 22479, ammonia).
  • Ultraviolet (UV) resistance for outdoor ISGs.
• Mechanical tests
  • Impact and mechanical integrity testing (e.g., pendulum hammer apparatus referenced).
• Electrical tests
  • Isolation resistance and rated DC/power-frequency withstand voltages.
  • Rated impulse sparkover voltage and lightning current withstand capability (see Table 1 for lightning impulse current parameters).
• Documentation, marking and installation instructions
  • Required technical documentation, installation guidance, marking and traceability.
• Electromagnetic compatibility (EMC)
  • Requirements ensuring ISGs do not adversely affect or be affected by EMC issues.
• Test reporting
  • Structure and content of test reports, including specimen description, test equipment, measured parameters and pass/fail statements.
• Normative annexes
  • Annex A: test flowchart; Annex B: detailed corrosion treatments; Annex C: UV tests; Annex D: applicability of previous tests.

Practical Applications and Who Uses This Standard

Typical practical applications where ISGs are specified include:

• Bonding to earth-termination systems of power and telecommunication installations
• Auxiliary earth electrodes for earth-fault devices
• Rail earth electrodes (power and DC railways)
• Measuring earth electrodes in laboratories
• Installations with cathodic protection or stray current systems
• Service entry masts for LV overhead cables and bypassing insulated pipeline couplings

Primary users:

• LPS designers and consulting engineers
• ISG manufacturers and component suppliers
• Independent test laboratories and certification bodies
• Utilities (power, rail), telecom operators, pipeline and industrial asset owners
• Installers and maintenance contractors

Related Standards

• IEC 62305 series (overall lightning protection design)
• ISO 22479 (humid sulphurous atmosphere treatment) - alignment noted in 2023 edition
• National or regional standards for hazardous/explosive atmospheres where additional requirements apply

Keywords: IEC 62561-3, isolating spark gaps, ISG, lightning protection system, LPSC, sparkover voltage, corrosion resistance, UV resistance, lightning current tests.