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Fully charged The application of BS 7671 to exterior lighting This article discusses the requirements of Section 714 and other regulations relating to exterior lighting; this will include equipment used to illuminate areas such as highway power supplies and street furniture.
with through wiring is applicable to outdoor lighting installations. Section 714 applies only to specific types of outdoor lighting installations such as street electrical furniture, street lighting, road signs and lighting arrangements in telephone kiosks, bus shelters and the like. Section 714 specifically excludes any application to temporary festoon lighting, luminaires fixed to the outside of buildings supplied directly from the internal wiring of that building (refer Fig 1) and road traffic signals (Regulation 714.1 refers). Protective measures
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n previous versions of BS 7671, outdoor lighting installations were included as part of Section 559 – Luminaires and lighting installations. However in Amendment 3, outdoor lighting installations are classified as being a special installation and are now the subject of the additional requirements of Section 714. It should be remembered that, like the requirements of other special installations, the requirements of Section 714 supplement or modify the general requirements contained in Parts 1 to 6 of the regulations. Consequently, where a regulation is not supplemented or modified by a regulation in Section 714, the requirements contained in parts 1 to 6 of BS 7671 will apply; for example, Regulation 559.5.3 dealing
Fig 1 An example of luminaires supplied directly from the internal wiring of a building
Similar to other types of special locations, Regulation 714.410.3.6 prohibits the use of the protective measures non-conducting locations and earth-free local equipotential bonding for outdoor lighting installations. Where the protective measure automatic disconnection of supply is used, Regulation 714.411.201 requires that all live parts of electrical equipment shall be protected by insulation or barriers or enclosures providing basic protection. Furthermore, Regulation 714.411.2.201 requires: • that unless the enclosure is in a location only accessible to skilled or instructed persons, the live parts of every accessible enclosure shall only be accessible with a key or a tool. It should be noted that this regulation applies to all enclosures forming part of the outdoor lighting installation and not just to luminaires • luminaires mounted at a height less than 2.8 m above ground level should be designed so that access to the light source shall only be possible after removing a barrier or an enclosure requiring the use of a tool • doors giving access to electrical equipment (such as lighting columns) and located less than 2.5 m above the ground shall be locked with a key or shall require the use of a tool for access. In addition, when the door is open, basic protection shall be provided by either the use of equipment having a degree of protection of IPXXB or IP2X or by installing a barrier or an enclosure giving the same degree of protection. Except for circuits supplying fixed equipment used in highway power supplies where a maximum disconnection time of 5 s is stated (Regulations 714.411.202 refers), Section 714 does not contain any specific requirement regarding maximum disconnection times. Consequently, where the protective measure is automatic disconnection of supply, the disconnection times given in Section 411 apply. This means, for example, that where a socket-outlet rated at Connections Summer 2015
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