![]()
1
Introduction
The latest edition of the Institution of Engineering and Technology (IET) Wiring Regulations has now grown to a massive 464-page document that defines the way in which all electrical installation work must be carried out. It does not matter whether the work is carried out by a professional electrician or an unqualified DIY enthusiast, the installation must still comply with the Wiring Regulations.
The current edition of the Regulations is BS 7671:2010 (Incorporating Amendment No. 1:2011) and is entitled Requirements for Electrical Installations – IET Wiring Regulations (Seventeenth Edition). Which is a bit of a mouthful to remember (!), and so it is normally referred to as The Green Book or The 1st Amendment to the 17th Edition.
Figure 1.1 Front cover of BS 7671:2010 incorporating Amendment No. 1:2011.
This British Standard is published with the full support of the BEC (i.e. the British Electrotechnical Committee – which is the UK national body responsible for formal standardization within the electrotechnical sector) in partnership with the BSI (i.e. the British Standards Institution – which has ultimate responsibility for all British Standards produced within this sector) and the Institution of Engineering and Technology (IET) – which, with more than 135,000 members, is Europe's largest grouping of professional engineers involved in power engineering, communications, electronics, computing, software, control, informatics and manufacturing.
The technical authority for this standard is the Joint IET/BSI Technical Committee (JPEL/64), which is responsible for all the work previously undertaken by the IET Wiring Regulations Committee and BSI Technical Committee PEL64.
Copyright is jointly held by BSI and the IET, and Amendment No. 1:2011 to BS 7671:2008 was issued on 1 July 2011 and came into effect on 1 January 2012.
| All installations that are designed after 31 December 2011 must comply with this edition, as amended and expanded. |
| Note: All references made in this book to the ‘Wiring Regulations’ or the ‘Regulation(s)’ – where not otherwise specifically identified – refer to BS 7671:2010, Incorporating Amendment No. 1:2011 Requirements for Electrical Installations. |
1.1 Historical background
The first public electricity supply in the UK was at Godalming in Surrey in November 1881 and mainly provided street lighting. At that time there were no existing rules and regulations available to control the installation, and so the electricity company just dug up the roads and laid the cables in the gutters. This particular electricity supply was discontinued in 1884.
On 12 January 1882, the steam-powered Holborn Viaduct Powerstation officially opened, and this facility supplied 110 V d.c. for both private consumption and street lighting. Once more, there was no one in authority to stipulate how the cables should be laid, and their positioning was, therefore, dependent on the electrician responsible for that particular section of the work.
Later in 1882, The Electric Lighting Clauses Act (modelled on the previous 1847 Gas Act) was passed by Parliament, and this enabled the Board of Trade to authorize the supply of electricity in any area by a local autho...
