scope:

Part 3 of IEC 62561 specifies the requirements and tests for isolating spark gaps (ISG) for lightning protection systems. ISGs can be used to indirectly bond a lightning protection system to other nearby metalwork where a direct bond is not permissible for functional reasons. Typical applications include the connection to • earth-termination systems of power installations, • earth-termination systems of telecommunication systems, • auxiliary earth electrodes of voltage-operated, earth fault circuit breakers, • rail earth electrode of power and DC railways, • measuring earth electrodes for laboratories, • installations with cathodic protection and stray current systems, • service entry masts for low-voltage overhead cables, • bypassing insulated flanges and insulated couplings of pipelines. This does not cover applications where follow currents occur. NOTE - Testing of components for an explosive atmosphere (as defined in IEC 60079-10) is not covered by this document.