Electrical
installations
Designing to the Wiring rules
Electrical
installations
Designing to the Wiring rules
COPYRIGHT
© Standards Australia International
All rights are reserved. No part of this work may be reproduced or copied in any form or by any means, electronic or mechanical, including photocopying, without the written permission of the publisher.
Published by Standards Australia International Ltd GPO Box 5420, Sydney, NSW 2001, Australia
First published as HB 301—2001.
Preface
AS/NZS 3000 Wiring rules is a performance-based standard, which sets out the minimum requirements for the design, construction, and testing of electrical installations. The requirements are intended to protect persons, livestock, and property from electric shock, fire and physical injury hazards.
This handbook includes typical electrical installation scenarios, and each of these has been developed to include a “complying solution”. In this sense a “complying solution” is one solution which meets the performance requirements of AS/NZS 3000.
As such, there are many ways of complying with AS/NZS 3000. This document has been produced as a design guide for commonly encountered electrical installations. While the design principles apply equally to larger and more complex installations, it is not the intention of this handbook to attempt to address the detailed design needs of those installations.
This handbook will be reviewed periodically to take account of the changes in design and installation procedures and relevant Standards.
The work of Bruce Walsh (Ballengearry Consulting Pty Ltd) who prepared this handbook, and the direction of Standards Australia, is recognized and greatly appreciated.
Contents
Foreword ... 4
Scope... 5
References ... 6
Section 1 The design and installation process... 8
1 The brief ... 9
2 The planning phase ... 11
2.1 Maximum demand assessments... 12
2.2 Voltage drop considerations ... 13
3 The design phase... 16
3.1 Introduction and overview... 17
3.2 Fault level and prospective short-circuit current... 21
3.3 Fault-loop impedance... 22
3.4 Residual current devices... 24
3.5 Discrimination and grading ... 25
3.6 Discrimination in practice ... 27
3.7 Earthing ... 29
3.8 Switchboards ... 31
3.9 Final subcircuits... 32
4 Installation... 34
5 Testing and verification... 34
6 Guidance notes for solutions ... 35
6.1 Format ... 35
6.2 Service and installation rules ... 35
6.3 Selection of cables ... 35
6.4 Fault ratings of switchboards... 39
6.5 Earthing ... 40
6.6 Distribution boards and final subcircuits... 40
6.7 Fault-loop impedance values ... 40
Appendix A Look up tables... 41
Tables A1 Typical fault levels and impedance... 41
A2 Assessment of maximum demand—ADMD method... 42
A3 Minimum cable csa in mm2 for K=111—Short circuit characteristics ... 43
A4 Cable impedance values for V 75 single-core conductors—Installed touching ... 44
A5 Cable impedance values for V 75 multicore cables—Circular conductors ... 45
A6 Maximum circuit lengths for 2% to 3% voltage drop, single-phase circuits... 46
A7 Maximum values of fault-loop impedance (Table B4.1 Wiring rules) ... 47
Appendix B Theoretical information... 48
B1 Prospective short-circuit current ... 48
B2 Fault loop calculation when the source impedance is not known ... 54
B3 Touch voltage ... 55
B4 Protective device characteristics ... 57
Section 2 Complying solutions ... 59
Part 1 Residential—Multiple detached units ... 59
Part 2 Residential—Multiple grouped units with common walls—Single level ... 89
Part 3 Residential—Multi (3) storey—18 units ... 119
Part 4 Retail development—Single level—10 units ... 149
Part 5 Multi (3) storey office building... 181
Part 6 Light industrial units—Detached—Single level ... 209
Part 7 Light industrial units—Grouped ... 239 Part 8 Pro-forma design record...Separate document
Foreword
This handbook contains the following sections:
Section 1 consists of a narrative which explains the process and procedure of designing an electrical installation of the type contained in this handbook. The phases of design include the brief, planning, the detailed design, and the narrative and flowcharts take the designer step by step through the process. The narrative includes theory and practice which the designer may apply to electrical designs generally. The requirements for testing and verification of the installation are also included and explained.
Section 2 consists of a suite of complying solutions which are detailed and include a short narrative where necessary to explain the detailed design further. The solutions have been presented using a common format and layout so that the designer following this document can readily adapt and modify the solution to suit a different application.
Similarly the designer may adapt the procedure in this document to develop other complying solutions, and to implement different formats and styles for presentation.
The complying solutions include:
1. Residential—Multiple detached units
2. Residential—Multiple grouped units with common walls—Single level 3. Residential—Multi (3) storey—18 units
4. Retail development—Single level—10 units 5. Multi (3) storey office building
6. Light industrial units—Detached—Single level 7. Light industrial units—Grouped
8. Pro-forma design record—Separate document
Sketches and records are presented to provide the designer with the reference material necessary
to make submissions to Electricity Distributors, and to document the installation.
This document includes the installation and testing details for the complying solutions which allows the designer to verify the installation as being complete.
The pro-forma design record has been provided as a separate document so it may be copied and used as necessary as an aid to designing electrical installations.
Scope
This document applies to electrical design, installation, and testing in general which is developed to comply with the requirements of AS/NZS 3000, Wiring rules.
In addition, there are State and Territorial legislature requirements that must be applied in the design of electrical installations. These requirements are generally incorporated in the Electricity Distributor Service and Installation Rules, and will be referred to in this document as the “Service Rules”.
While the requirements and terminology of the Electricity Distributor Service and Installation Rules have been acknowledged, it is not intended that this document address every possible combination of these rules, and it is to that extent intended to be generic.
The designer using this document is to check the requirements of the Electricity Distributor Service and Installation Rules, and is to check with the Electricity Distributor for any special requirements. The designs may be modified as necessary.
This Handbook is not a replacement for AS/NZS 3000, and the user must refer to AS/NZS 3000 for guidance on the application of the Standard in all cases.
The technical information contained in the complying solutions is not a replacement for the AS/NZS 3008.1 series, and the user must refer to the appropriate part of that standard for guidance on the selection of cables for Australia and New Zealand.
This handbook is not intended to address the detailed design and planning requirements for: a) High voltage electrical installation.
b) Prospective short-circuit currents exceeding 20 kA. c) Hazardous locations (see the AS/NZS 2381 series).
Where these electrical installations arise, an electrical designer experienced in the type of project envisaged should be used to undertake the planning and design.
This is a free preview. Purchase the entire publication at the link below:
Looking for additional Standards? Visit SAI Global Infostore
Subscribe to our Free Newsletters about Australian Standards® in Legislation; ISO, IEC, BSI and more Do you need to Manage Standards Collections Online?
Learn about LexConnect, All Jurisdictions, Standards referenced in Australian legislation Do you want to know when a Standard has changed?
Want to become an SAI Global Standards Sales Affiliate? Learn about other SAI Global Services:
LOGICOM Military Parts and Supplier Database
Metals Infobase Database of Metal Grades, Standards and Manufacturers Materials Infobase Database of Materials, Standards and Suppliers Database of European Law, CELEX and Court Decisions
Need to speak with a Customer Service Representative - Contact Us
This is a free 6 page sample. Access the full version at http://infostore.saiglobal.com.
