JEC IEC63374 Edition 1.0 2025-10 INTERNATIONAL STANDARD NORME INTERNATIONALE Nuclear power plants - Instrumentation systems important to safety Characteristics and test methods of nuclear reactorreactivity meters Centrales nucleaires - Systemes d'instrumentation importants pour la surete - Caracteristigques et methodesd'essaides reactimetresd'unreacteurnucleaire IEC 63374:2025-10(en-fr) ICS 27.120.20, 27.120.10 ISBN 978-2-8327-0691-6 THIS PUBLICATIONIS COPYRIGHTPROTECTED Copyright@2025IEC,Geneva,Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEc or enquiry about obtaining additional rights to this publication, please contact the address below or your local IEC member National Committee for further information. Droits de reproduction réserves. Sauf indication contraire, aucune partie de cette publication ne peut etre reproduite ni utilisee sous quelque forme que ce soit et par aucun procede, electronique ou mecanique, y compris la photocopie et les microfilms, sans 'accord écrit de IIEC ou du Comite national de IIEC du pays du demandeur. Si vous avez des questions sur le copyright de lIEC ou si vous desirez obtenir des droits supplementaires sur cette publication, utilisez les coordonnees ci-apres ou contactez le Comite national de IEC de votre pays de residence. IEC Secretariat Tel.: +41 22 919 02 11 3, rue de Varembé [email protected] www.iec.ch CH-1211 Geneva 20 Switzerland About the IEC The International Electrotechnical Commission (lEC) is the leading global organization that prepares and publishes International Standards for all electrical, electronic and related technologies. AboutIECpublications The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the latest edition, a corrigendum or an amendment might have been published IEC publications search - IEc Products&Services Portal-products.iec.ch webstore.iec.ch/advsearchform Discover our powerful search engine and read freely all the The advanced search enables to find IEC publications by publications previews, graphical symbols and the glossary. With a subscription you will always have access to up to a variety of criteria (reference number, text, technical committee, ...).It also gives information on datecontenttailoredtoyourneeds projects, replaced and withdrawn publications. Electropedia-www.electropedia.org IEC JustPublished-webstore.iec.ch/justpublished The world's leading online dictionary on electrotechnology, Stay up to date on all new IEC publications. Just Published and French, with equivalent terms in 25 additional languages. details all new publications released. Available online and once a month by email. Also known as the International Electrotechnical Vocabulary (IEV) online. IEC Customer ServiceCentre-webstore.iec.ch/csc If you wish to give us your feedback on this publication or need further assistance, please contact the Customer Service Centre: [email protected]. A propos de IIEC La Commission Electrotechnique Internationale (lEC) est la premiere organisation mondiale qui élabore et publie des Normes internationales pour tout ce qui a trait a 'electricite, a r'electronique et aux technologies apparentees. A propos des publications IEc Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possedez I'edition la plus recente, un corrigendum ou amendement peut avoir ete publie. RecherchedepublicationsIEc IEc Products & Services Portal -products.iec.ch webstore.iec.ch/advsearchform Decouvrez notre puissant moteur de recherche et consultez La recherche avancee permet de trouver des publications gratuitement tous les apercus des publications, symboles IEC en utilisant differents criteres (numero de reference, graphiques et le glossaire. Avec un abonnement, vous aurez