Overview
IEC 62561-3:2017 - part of the Lightning Protection System Components (LPSC) series - specifies the requirements and test procedures for isolating spark gaps (ISG) used in lightning protection systems (LPS). ISGs provide a controlled, indirect bond between an LPS and nearby metalwork where a direct electrical connection is not permissible for functional reasons. This second edition (2017) updates the first edition (2012) and introduces a new classification for ISG installation location plus an updated flow chart of tests.
Keywords: IEC 62561-3, isolating spark gaps, ISG requirements, lightning protection, LPSC, lightning protection standard.
Key topics and technical requirements
The standard defines performance, testing and documentation expectations for ISGs, including:
- Scope and intended use - typical applications such as earth-termination systems (power and telecom), rail earth electrodes, laboratory measuring earths, cathodic protection systems, service entry masts, and bypassing insulated flanges/couplings.
- Classification - by lightning-current carrying capability and by installation location (new in this edition).
- Environmental requirements and tests - resistance to salt mist, humid sulphurous and ammonia atmospheres, and ultraviolet (UV) exposure for outdoor ISGs.
- Mechanical tests - impact and hammer tests to verify physical robustness.
- Electrical tests - isolation resistance, rated DC and power-frequency withstand voltage, rated impulse sparkover voltage and lightning current withstand tests.
- Marking, installation instructions and EMC - required identification, packaging and guidance for correct field use; electromagnetic compatibility considerations.
- Test reporting - required structure and content of laboratory test reports; normative flow chart of test sequences is included.
Practical applications and who uses this standard
IEC 62561-3 is practical and directly applicable for:
- Manufacturers of isolating spark gaps and lightning protection components - design, type testing and compliance.
- Test labs and certification bodies - to conduct the environmental, mechanical and electrical tests and produce compliant test reports.
- Designers and consultants of lightning protection systems - specifying suitable ISGs for installations where direct bonding is not allowed.
- Installers and facility engineers - understanding installation classes, marking and performance limits to ensure safe, compliant bonding arrangements.
- Industry sectors - power utilities, telecommunications, railways, petrochemical and pipeline operators, laboratories and any facility using cathodic protection or insulated pipeline couplings.
Related standards
Using IEC 62561-3 helps ensure ISGs meet internationally recognized safety, performance and testing criteria for reliable lightning protection and compliant indirect bonding.
Open preview (PDF)Lightning protection system components (LPSC) - Part 3: Requirements for isolating spark gaps (ISG)
