BAS HD 60364-4-443:2017

The rules of IEC 60364-4-44 are intended to provide requirements for the safety of electrical installations in the event of voltage disturbances and electromagnetic disturbances generated for different specified reasons. The rules of this IEC 60364-4-44 are not intended to apply to systems for distribution of energy to the public, or power generation and transmission for such systems (see the scope of IEC 60364-1) although such disturbances may be conducted into or between electrical installations via these supply systems. Clause 443 specifies requirements for protection of electrical installations against transient overvoltages of atmospheric origin transmitted by the supply distribution system including direct strikes to the supply system and against switching overvoltages. Clause 443 does not specify requirements for protection against transient overvoltage due to direct or nearby lightning strokes on the structure. NOTE For risk management for protection against transient overvoltage due to direct or nearby lightning strokes on the structure, see IEC 62305-2.