scope:

NEN-EN-IEC 62561-3 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.