Christopher Kitcher - Electrical Installation Calculations: Advanced

Electrical Installation Calculations: AdvancedElectrical Installation Calculations: AdvancedFor technical certificate and NVQ level 3 Christopher Kitcher and A.J. Watkins Eighth Edition Eighth edition published 2014 by Routledge 2 Park Square, Milton Park, Abingdon, Oxon OX14 4RN and by Routledge 711 Third Avenue, New York, NY 10017 Routledge is an imprint of the Taylor & Francis Group, an informa business 2014 Christopher Kitcher and A. J. Watkins The right of Christopher Kitcher and A. J. Watkins to be identified as authors of this work has been asserted by him/her in accordance with sections 77 and 78 of the Copyright, Designs and Patents Act 1988.

All rights reserved. No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. Trademark notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. First edition published 1957 Seventh edition published by Elsevier 2009 British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging in Publication Data Kitcher, Chris. Electrical installation calculations : advanced : for technical certificate and NVQ level 3 / Christopher Kitcher and A. Watkins. Watkins.

Eighth edition. pages cm 1. Electric wiringMathematics. 2. Electric wiringStandardsGreat Britain. 3.

Electrical engineersCertificationGreat Britain. 4. National Vocational Qualifications (Great Britain) I. Watkins, A. J. Title. Title.

TK3221.K57 2014 621.31924dc23 2013021029 ISBN: 9780415810036 (pbk) ISBN: 9781315863122 (ebk) Table of Contents Being able to carry out mathematical calculations is a vital part of electrical installation courses and indeed electrical installation work. The structure of electrical installation courses continually changes as do the course titles and numbers, however electrical science remains the same, and like it or not anyone wanting to become an electrician will need to have a good understanding of how to carry out electrical calculations. The calculations which need to be performed vary from those which an electrician needs almost on a daily basis, such as cable calculation or the amount of energy required to run a particular piece of equipment, to more complex calculations such as those required for electromagnetism. This book will show you how to carry out these calculations as simply as possible using electronic calculator methods. These methods will be useful both in the classroom and the workplace. It is not necessary for you to have a deep understanding of how the mathematical functions are performed.

Each topic is shown using a step-by-step process with lots of exercises provided to give you the opportunity to test yourself at the end of each chapter. This edition has been completely updated to the 17th edition of BS 7671 amendment 1: 2011 and the IET On-Site Guide, useful references are made to these documents throughout. It does not matter which electrical course you are attending, this book along with the basic calculations book will be invaluable. Throughout books 1 and 2 the use of a calculator is encouraged. Your calculator is a tool, and like any tool practice is required to perfect their use. A scientific calculator will be required, and although they differ in the way the functions are carried out, the end result is the same.

The examples are given using a Casio fx-83MS. The character printed on the button is the function performed when the button is pressed. To use the small letter functions on the top of any button the shift button must be used. Practice is important. Syntax error: will appear when the figures are entered in the wrong order. x2: will multiply a number by itself, eg 6 6 = 36.

On the calculator this would be 6 x2 = 36. When a number is multiplied by itself it is said to be squared. x2: will multiply a number by itself and then the total by itself again, eg when we enter 4 on calculator x3 = 64. When a number is multiplied in this way it is said to be cubed. : will give you the number which achieves your total by being multiplied by itself, eg This is said to be the square root of a number, and is the opposite of squared. x1: will divide 1 by a number, eg . x1: will divide 1 by a number, eg .

This is the reciprocal button and is useful in this book for finding the resistance of resistors in parallel and capacitors in series. EXP: is for the powers of 10 function, eg 25 1000 = 25 EXP 103 = 25 000. Enter into your calculator 25 EXP 3 = 25000. (Do not enter the or the number 10.) If a calculation shows 103, eg 25 103, enter 25 EXP 3 = (0.025) (when using EXP if a minus is required use the button ()). Brackets: these should be used to carry out a calculation within a calculation. Example 1 3 4 = 2 6 3 4 = 2 ? Transpose to find ?Example 2 Step 1 2 6 = 4 ? Step 2 AnswerExample 3 5 8 6 = 3 20 ? Step 1 move 3 20 away from unknown value, as the known values move across the = sign they must move to bottom of equation Step 2 Carry out the calculation Therefore 5 8 6 = 240 or 3 20 4 = 240 or 5 8 6 = 3 20 4 In the United Kingdom and the rest of Europe the units for measuring different properties are known as SI units. Example 1 3 4 = 2 6 3 4 = 2 ? Transpose to find ?Example 2 Step 1 2 6 = 4 ? Step 2 AnswerExample 3 5 8 6 = 3 20 ? Step 1 move 3 20 away from unknown value, as the known values move across the = sign they must move to bottom of equation Step 2 Carry out the calculation Therefore 5 8 6 = 240 or