scope:

The standard applies to the design and erection of electrical power installations in systems with nominal voltages above 1 kV AC. For the purpose of interpreting this standard an Electrical Power Installation is considered to be one of the following: a) A generating station or stations located on a single site. The installation includes generator and transformer units with all associated switchgear and all electrical auxiliary systems. Connections between stations which are part of a transmission or distribution network are however excluded. b) A closed electrical operating area or substation in a transmission or distribution network. Where switchgear and/or transformers are located outside a closed electrical operating area this is also taken to be an installation. c) The electrical system of a factory, industrial plant or other industrial or commercial premises. Line or cable connections between closed electrical areas or substations are taken to be part of the installation except where such connections form part of an interconnected network and run between physically separate parts of an industrial plant.