Electrical Installation Designs (eBook)

Bill Atkinson, Gary Gundry, Roger Lovegrove (Autoren)

eBook Download: EPUB

2012 | 4. Auflage
272 Seiten
Wiley (Verlag)
978-1-118-47776-2 (ISBN)

Infos

A practical and highly popular guide for electrical contractors of small installations, now fully revised in accordance with the latest wiring regulations

The book is a clearly written practical guide on how to design and complete a range of electrical installation projects in a competitive manner, while ensuring full compliance with the new Wiring Regulations (updated late 2008). The updated regulations introduced changes in terminology, such as ‘basic’ and ‘fault protection’, and also changed the regulation numbers. This new edition reflects these changes. It discusses new sections covering domestic, commercial, industrial and agricultural projects, including material on marinas, caravan sites, and small scale floodlighting. This book provides guidance on certification and test methods, with full attention given to electrical safety requirements.   Other brand new sections cover protective measures, additional protection by means of RCDs, the new cable guidelines for thin wall partitions and Part P of the Building Regulations. 

• Provides simple, practical guidance on how to design electrical installation projects, including worked examples and case studies
• Covers new cable guidelines and Part P of the Building Regulations (Electrical Installations) in line with 17^th edition of the Wiring Regulations BS 7671:2008
• New chapters on protective measures and additional protection by means of RCDs (residual current devices)
• Features new wiring projects such as marinas, caravan sites and small scale floodlighting and street lighting
• Fully illustrated, including illustrations new to the fourth edition 

Mr. Bill Atkinson (deceased) Bill Atkinson was the writer's pseudonym used by Alan Smith, the original author of the book. He worked in the electrical installation industry and at the NICEIC.

Mr. Roger Lovegrove, Consultant, Surrey, UK Roger Lovegrove is an electrical consultant. He is a member of the Electrical Contractors' Association techinical committees and of the joint IEE/BSI Wiring Regulations committee. With his vast knowledge in this area of electrical engineering, he has updated Bill Atkinson’s original text for this fourth edtition.

Mr. Gary Gundry,   Senior Engineer, Electrical Safety Council, UK Mr Gundry worked for Seeboard and Eastern Electricity, before becoming a lecturer at Lowestoft College, teaching electrical contracting and electrical engineering up to HNC level. He joined NICEIC in 1999 after spending three years as a Director and Qualified Supervisor of a business enrolled as an Approved Contractor, where he worked in the Standards division on the NICEIC Technical Manual. He is now Senior Engineer at Electrical Safety Council.

Mr. Martyn Allen, Senior Engineer, Electrical Safety Council Martyn Allen's experience in the electrical installation industry spans 30 years. He served an apprenticeship and worked as an electrician with British Coal, spent 16 years in engineering insurance risk management and then joined the Electrical Safety Council. He is a Chartered Electrical Engineer and Corporate Member of the IET. He is a member of the Joint Technical Committee JPEL/64 Panel C – Shock Protection and Isolation and Switching.

Textauszug

Preface to the Fourth Edition

There are many books on electrical installation practice where the focus is on calculations and regulations. Electrical Installation Designs has been written from a different viewpoint. Typical projects are examined to produce designs that will fit current standards.

Most electrical contractors have an understanding of requirements related to their own regular everyday activities, where work is carried out using rule-of-thumb methods. Repetitive designs are used. Many installers claim that they are not designers and show concern that they are now required to certify the adequacy of an installation design.

In practice, problems only arise when an unusual project is undertaken or there is a change in regulations.

There is no harm in using a standardised design, rather in the way that an experienced cook uses a published recipe for a cake. Electrical Installation Designs is a book of recipes. The installer may select a design that corresponds as near as possible to the contract in hand and take up such technical and regulatory advice as is required. This will reduce the need for lengthy calculations and detailed study of BS 7671, Requirements for Electrical Installations (IET Wiring Regulations).

Most basic electrical installations may be completed by a competent person, with appropriate guidance to avoid serious problems and hazards.

Project chapters illustrate methods that could be used for particular types of installation ranging from a house to an industrial workshop. The ideas are by no means exclusive. Alternative solutions are always possible. In many instances carrying out detailed calculations and utilising different circuitry will be more profitable. By their very nature, simplified examples of fictional projects can only produce generalised results.

The book contains special chapters on earthing, isolation and switching and overcurrent protection, which give a down to earth interpretation of the regulations.

Electrical installation students and non-electrical associates in the construction industry will appreciate the user-friendly approach. Nevertheless, this is not a do-it-yourself book for the untrained person. Warnings are therefore given where more specialised study is necessary. For example, readers are advised not to embark on installations in hazardous areas (such as petrol filling stations) without further training. Apart from moral implications and contractual risks, statutory requirements are such that incompetent work may carry criminal penalties.

Although the emphasis is on tried and tested methods, some new techniques are introduced. The most significant is the option for tree circuitry as an alternative to the ring final circuit. This is the first book to give designers the opportunity to compare the advantages of the tree system for both domestic and commercial installations. In recent years, consumer requirements have changed. It is essential that the industry keeps an open mind on changes in traditional wiring practice. Introduced in this fourth edition are new chapters on Residual Current Devices and, for those readers who require a basic understanding of circuit design, a chapter explaining the process for carrying out simple cable design calculations.

Amendments

The Institution of Electrical Engineers (IEE) joint wiring regulations committee amended BS 7671: 1992 (16th edition) in 1994, 1997 and 1999. In 2001, the standard was renamed BS 7671: 2001 with further amendments, and minor amendments were made again in 2002.

In 2008, a complete review of the 16th edition saw the publication of the 17th edition: BS 7671: 2008. The first amendment to the 17th edition was published in 2011 and came fully into force on 1 January 2012. This latest amendment also introduced the rebranded name of the IEE, namely the IET (Institution of Engineering and Technology). The most recent edition of BS 7671 incorporates all alterations and additions to the European HD 384 series of standards.

As is often the case, many of the changes are of a minor nature in order to harmonise with other standards. However, significant changes were introduced in BS 7671: 2008 (17th edition) with several other significant changes being introduced in its first amendment, in 2011. These are summarised in the following tables – Table A.1 summarises the changes introduced by BS 7671: 2008 (17th edition) and Table A.2 summarises the significant changes introduced by Amendment 1 to BS 7671: 2008:

Table A.1 Summary of changes introduced by BS 7671: 2008 (17th edition).

BS 7671 reference

Subject

Summary of notable change/new content

General

Regulation numbering system

The 17th edition introduced the adoption of the IEC numbering system, in which the Regulation numbers are separated by a decimal point, rather than a hyphen as was previously the case.

Chapter 41

Protection against electric shock

Chapter was rewritten. Protection against direct contact – was replaced by basic protection. Protection against indirect contact – was replaced by fault protection. Introduction of term ‘Additional protection’. Socket-outlets with a rated current not exceeding 20 A and intended for general use by ordinary persons must be protected by 30 mA RCDs. Mobile equipment having a current rating of 32 A or less for use outdoors must also have 30 mA RCD protection.

Chapter 52

Selection and erection of wiring systems

For installations not under the supervision of a skilled or instructed person, such as domestic or similar installations, cables that are buried in a wall or partition at a depth of 50 mm or less and are not enclosed in earthed metallic covering (metallic armouring), earthed conduit, earthed trunking or have mechanical protection capable of resisting nails, screws or the like, are required to be protected by a 30 mA RCD as well as being installed in the so-called ‘safe zones’. Similarly cables that are installed in metal framed walls require 30 mA RCD protection if not otherwise protected by earthed metallic covering, earthed conduit, earthed trunking or have mechanical protection capable of resisting nails, screws or the like, to be protected by a 30 mA RCD, unless the installation is under the control of skilled or instructed persons, such as office buildings and industrial premises.

Section 559

Luminaires and lighting

A new section applicable to all general lighting installations as appropriate to particular locations and structures. Requirements for fixed outdoor lighting, highway power supplies and street furniture are also included, which were previously in Part 6.

Part 6

Inspection and testing

Was previously Part 7.

Part 7

Special installations or locations

Was previously Part 6. 701 – Locations containing a bath or a shower. Zones 0, 1 and 2 as defined in the 16th edition were retained. Zone 3 was removed. All circuits supplying equipment in bathrooms and shower rooms are required to be protected by 30 mA RCDs. Supplementary bonding is no longer required, provided all of the following three conditions are met: • all final circuits of the location are protected by a 30 mA RCD; • all final circuits of the location meet the required disconnection times; • main bonding of services within the property is correctly installed.

SELV (separated extra-low voltage) socket-outlets and shaver socket-outlets are permitted outside Zone 1 230 V socket-outlets are permitted, provided they are more than 3 metres horizontally from the boundary of zone 1. 708 – Electrical installations in caravan/camping parks and similar locations. Formerly caravans, motor caravans and caravan parks in the 16th edition.

New Sections were added as follows: 709 – Marinas and similar locations; 711 – Exhibitions, shows and stands; 712 – Solar photovoltaic (PV) power supply systems; 717 – Mobile or transportable units; 721 – Electrical installations in caravans and motor caravans; 740 – Temporary electrical installations for structures, amusement devices and booths at fairgrounds, amusement parks and circuses.

Table A.2 Summary of changes introduced by Amendment 1 to BS 7671: 2008.

BS 7671 reference

Subject

Summary of notable change/new content

General

Regulation numbering system

In order to further implement changes to the requirements given in the International (IEC) and European (CENELEC) base documents, a number of the requirements contained in BS 7671 are particular to the United Kingdom. Those Regulations are identified via a ‘10X’ suffix. For example, Regulation 522.6.100.

General

References to ESQCR 2002

Amendments have been made throughout BS 7671 to clarify the requirements of the Electricity Safety, Quality...

Produkt-Details

• Erscheint lt. Verlag: 26.11.2012
• Sprache: englisch
• Themenwelt: Technik ► Elektrotechnik / Energietechnik
• Schlagworte: Circuit Theory & Design • Electrical & Electronics Engineering • Elektrotechnik • Elektrotechnik u. Elektronik • Qualität u. Zuverlässigkeit • Qualität u. Zuverlässigkeit • Quality & Reliability • Schaltkreise - Theorie u. Entwurf • Schaltkreistechnik
• ISBN-10: 1-118-47776-6 / 1118477766
• ISBN-13: 978-1-118-47776-2 / 9781118477762