1、 AMERICAN NATIONAL STANDARD ANSI/ISA-61241-0 (12.10.02)-2006 (R2011) Electrical Apparatus for Use in Zone 20, Zone 21 and Zone 22 Hazardous (Classified) Locations General Requirements Approved 29 March 2011 ANSI/ISA-61241-0 (12.10.02)-2006 (R2011), Electrical Apparatus for Use in Zone 20, Zone 21 an
2、d Zone 22 Hazardous (Classified) Locations General Requirements ISBN: 978-1-936007-88-2 Copyright 2011 by IEC and ISA. Not for resale. Printed in the United States of America. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means (ele
3、ctronic mechanical, photocopying, recording, or otherwise), without the prior written permission of the Publisher. ISA 67 Alexander Drive P.O. Box 12277 Research Triangle Park, North Carolina 27709 - 3 - ANSI/ISA-61241-0 (12.10.02)-2006 (R2011) Preface This preface, as well as all footnotes and anne
4、xes, is included for information purposes and is not part of ANSI/ISA-61241-0 (12.10.02)-2011. This document has been prepared as part of the service of ISA toward a goal of uniformity in the field of instrumentation. To be of real value, this document should not be static but should be subject to p
5、eriodic review. Toward this end, the Society welcomes all comments and criticisms and asks that they be addressed to the Secretary, Standards and Practices Board; ISA; 67 Alexander Drive; P. O. Box 12277; Research Triangle Park, NC 27709; Telephone (919) 549-8411; Fax (919) 549-8288; E-mail: standar
6、dsisa.org. The ISA Standards and Practices Department is aware of the growing need for attention to the metric system of units in general, and the International System of Units (SI) in particular, in the preparation of instrumentation standards. The Department is further aware of the benefits to USA
7、 users of ISA standards of incorporating suitable references to the SI (and the metric system) in their business and professional dealings with other countries. Toward this end, this Department will endeavor to introduce SI-acceptable metric units in all new and revised standards, recommended practi
8、ces, and technical reports to the greatest extent possible. Standard for Use of the International System of Units (SI): The Modern Metric System, published by the American Society for Testing temperature tested under 500 mm dust layer, for use in Zone 21 . 57 30.5 Apparatus type of protection “tD“,
9、Practice B (see IEC 61241-1) for use in Zone 22 . 57 30.6 Apparatus type of protection “tD“, Practice A (see IEC 61241-1) for use in Zone 22 . 57 Annex A (informative) Common standards Safety requirements for electrical equipment 59 Annex B (informative) Equipment grounding. 61 Annex C (informative)
10、 United States major deviations. 63 Bibliography . 71 This page intentionally left blank. - 13 - ANSI/ISA-61241-0 (12.10.02)-2006 (R2011) Foreword All text of IEC 61241-0:2004 (1stedition) is included. U.S. National Deviations are shown by strikeout through text deleted and underline under text adde
11、d. There are three annexes in this standard. All are informative and are not considered part of this standard. This page intentionally left blank. - 15 - ANSI/ISA-61241-0 (12.10.02)-2006 (R2011) 1 Scope This standard part of IEC 61241 specifies general requirements for the design, construction, test
12、ing and marking of which is applicable to electrical apparatus protected by any recognized safeguard protection technique for use in areas where combustible dust may be present in quantities that could lead to a fire or explosion hazard. This standard is supplemented or modified by the following sta
13、ndards parts of IEC 61241 concerning specific types of protection: ANSI/ISA-61241-1 (12.10.03), Electrical Apparatus for Use in Zone 21 and Zone 22 Hazardous (Classified) Locations Protection by Enclosures “tD” Part 1: Protection by enclosures tD ANSI/ISA-61241-2 (12.10.06), Electrical Apparatus for
14、 Use in Zone 21 and Zone 22 Hazardous (Classified) Locations Protection by Pressurization “pD” Part 2: Protection by pressurization pD (under consideration) ANSI/ISA-61241-11 (12.10.04), Electrical Apparatus for Use in Zone 20, Zone 21, and Zone 22 Hazardous (Classified) Locations Protection by Intr
15、insic Safety “iD” Part 11: Intrinsically safe apparatus ANSI/ISA-61241-18 (12.10.07), Electrical Apparatus for Use in Zone 20, Zone 21 and Zone 22 Hazardous (Classified) Locations Protection by Encapsulation “mD” Part 18: Protection by encapsulation mD NOTE IEC 61241-14 gives guidance on the selecti
16、on and installation of the apparatus. Apparatus within the scope of this standard may also be subjected to additional requirements in other standards for example, IEC 60079-0. The application of electrical apparatus in atmospheres which may contain explosive gas as well as combustible dust, whether
17、simultaneously or separately, requires additional protective measures. This standard does not specify requirements for safety, other than those directly related to the explosion risk. Where the apparatus has to meet other environmental conditions, for example, protection against ingress of water and
18、 resistance to corrosion, additional methods of protection may be necessary. The method used is not to adversely affect the integrity of the enclosure. This standard does not apply to dusts of explosives that do not require atmospheric oxygen for combustion, or to pyrophoric substances. This standar
19、d is not applicable to electrical apparatus intended for use in underground parts of mines as well as those parts of surface installations of such mines endangered by firedamp and/or combustible dust. This standard does not take account of any risk due to an emission of flammable or toxic gas from t
20、he dust. Electrical apparatus and Ex components for use in explosive dust atmospheres shall also comply with the applicable requirements for similar apparatus for use in unclassified locations. ANSI/ISA-61241-0 (12.10.02)-2006 (R2011)- 16 - NOTE Requirements for safety of electrical equipment in ord
21、inary (unclassified) locations can be found in ANSI Standards, NEMA Standards, Federal Regulations, etc. Apparatus listed by a Nationally Recognized Testing Laboratory is considered to meet the applicable requirements found in these standards. A list of commonly applied standards is shown in informa
22、tive Annex A. 2 Normative References The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60034-5:
23、2000, Rotating electrical machines Part 5: Degrees of protection provided by the integral design of rotating electrical machines (IP code) Classification IEC 60079-0:2004, Electrical apparatus for explosive gas atmospheres - Part 0: General requirementsANSI/ISA-60079-0 (12.00.01)-2005, Electrical Ap
24、paratus for Use in Class I, Zones 0, 1 based upon the frequency and duration of the occurrence of explosive dust/air atmospheres 3.16 Zone 20 place in which an explosive atmosphere in the form of a cloud of combustible dust in air is present continuously, or for long periods or frequently an area wh
25、ere combustible dust or ignitable fibers and flyings are present continuously or for long periods of time in quantities sufficient to be hazardous 3.17 Zone 21 place in which an explosive atmosphere in the form of a cloud of combustible dust in air is likely to occur, occasionally, in normal operati
26、onan area where combustible dust or ignitable fibers and flyings are likely to exist occasionally under normal operation in quantities sufficient to be hazardous 3.18 Zone 22 place in which an explosive atmosphere in the form of a cloud of combustible dust in air is not likely to occur in normal ope
27、ration but, if it does occur, will persist for a short period only an area where combustible dust or ignitable fibers and flyings are not likely to occur under normal operation in quantities sufficient to be hazardous 3.19 cable entry gland device permitting the introduction of one or more electric
28、and/or fibre optics cables into an electrical apparatus so as to maintain the relevant type of protection 3.20 conduit entry means of introducing a conduit into an electrical apparatus so as to maintain the relevant type of protection 3.21 compression element element of a cable entry gland acting on
29、 the sealing ring to enable the latter to fulfil its function 3.22 clamping device element of a cable entry gland for preventing tension or torsion in the cable from being transmitted to the connections - 21 - ANSI/ISA-61241-0 (12.10.02)-2006 (R2011) 3.23 sealing ring ring used in a cable or conduit
30、 entry to ensure the sealing between the entry and the cable or conduit 3.24 terminal compartment separate compartment or part of a main enclosure, communicating, or not, with the main enclosure, and containing connection facilities 3.25 connection facilities terminals screws and other parts, used f
31、or the electrical connection of conductors of external circuits 3.26 bushing insulating device carrying one or more conductors through an internal or external wall of an enclosure 3.27 cell assembly of electrodes and electrolyte that constitutes the smallest electrical unit of a battery 3.28 primary
32、 cell or battery electrochemical system capable of producing electrical energy by chemical reaction 3.29 secondary cell or battery electrically rechargeable electrochemical system capable of storing electrical energy and delivering it by chemical reaction 3.30 open cell or battery secondary cell, or
33、 battery, having a cover provided with an opening through which gaseous products may escape IEV 486-01-18, modified 3.31 sealed valve-regulated cell or battery cell or battery which is closed under normal conditions, but which has an arrangement which allows the escape of gas if the internal pressur
34、e exceeds a predetermined value NOTE The cell cannot normally receive an addition to the electrolyte. IEV 486-01-20, modified ANSI/ISA-61241-0 (12.10.02)-2006 (R2011)- 22 - 3.32 sealed gas-tight cell or battery a cell or battery which remains closed and does not release either gas or liquid when ope
35、rated within the limits of charge or temperature specified by the manufacturer IEV 486-01-21, modified NOTE 1 Such cells and batteries may be equipped with a safety device to prevent dangerously high internal pressure. The cell or battery does not require addition to the electrolyte and is designed
36、to operate during its life in its original sealed state. NOTE 2 The above definition is taken from EN 50020 ANSI/ISA-60079-11. It differs from IEV definitions 486-01-20 and IEV 486-01-21 by virtue of the fact it applies to either a cell or battery. 3.33 battery assembly of two or more cells electric
37、ally connected to each other to increase the voltage or capacity NOTE Where the terms “cell” or “cells” are used, the text refers to individual single cells. Where the terms “battery” or “batteries” is used, the text refers to both cells and batteries. 3.34 capacity quantity of electricity or electr
38、ic charge, which a fully charged battery can deliver under specified conditions 3.35 nominal voltage (of a cell or battery) voltage specified by the manufacturer 3.33 maximum open circuit voltage (of a cell or battery) volatage which is the maximum attainable voltage under normal conditions, that is
39、, from either a new primary cell, or a secondary cell just after a full charge NOTE See Table 3 and Table 4 which show the maximum open circuit voltage for acceptable cells. 3.37 charging act of forcing current through either a secondary cell or battery in the opposite direction to the normal flow t
40、o restore the energy stored originally 3.38 reverse charging act of forcing current through either a primary cell or secondary cell in the same direction as the normal flow NOTE For example, in an expired battery. 3.39 deep discharge event which reduces a cell voltage below that recommended by the c
41、ell or battery manufacturer - 23 - ANSI/ISA-61241-0 (12.10.02)-2006 (R2011) 3.40 inherently safe (ihs) cell (or battery) primary cell or battery in which the short-circuit current and maximum surface temperature are limited to a safe value by its internal resistance 3.41 Ex component part of electri
42、cal apparatus or a module (other than an Ex cable gland), which is not intended to be used alone and requires additional consideration when incorporated into electrical apparatus or systems for use in explosive atmospheres part of electrical apparatus for potentially explosive atmospheres, which is
43、not intended to be used alone in such atmospheres and requires additional certification when incorporated into electrical apparatus or systems for use in potentially explosive atmospheres 3.42 “X“ symbol symbol used as a suffix to a certificate reference to denote special conditions for safe use 3.4
44、3 “U“ symbol “U“ is the symbol used as a suffix to a certificate reference to denote an Ex component. NOTE - The symbols “X“ and “U“ should not be used together. 3.44 certificate document that assures the conformity of a product, process, system, person, or organisation with specified requirements N
45、OTE 1 The certificate may be either the suppliers declaration of conformity, or the purchasers recognition of conformity, or certification (as a result of action by a third party) as defined in ISO/IEC 17000. document confirming that the apparatus is in conformity with the requirements, the type tes
46、ts and, where appropriate, the routine tests in the standard referred to therein NOTE 1 A certificate can relate to Ex apparatus or an Ex component. NOTE 2 A certificate may be produced by the manufacturer, the user, or a third party, for example, an IEC Ex Accepted Certification Body, a national ce
47、rtification body, or an authorized person. 3.45 continuous operating temperature (COT) maximum temperature which ensures the stability and integrity of the material for the expected life of the apparatus, or part, in its intended application 3.46 service temperature temperature reached when the appa
48、ratus is operating at rated conditions NOTE Each apparatus may reach different service temperatures in different parts. ANSI/ISA-61241-0 (12.10.02)-2006 (R2011)- 24 - 4 Construction 4.1 General Electrical apparatus for use in potentially explosive dust atmospheres shall comply with the requirements
49、of this standard. NOTE If the electrical apparatus has to withstand particularly adverse service conditions (for example rough handling, humidity effects, ambient temperature variations, effects of chemical agents, corrosion) these should be specified to the manufacturer by the user and are not the responsibility of the testing station. 4.2 Principles for design and testing of apparatus for use in Zone 20 Apparatus for Zone 20 needs special consideration. The apparatus shall be designed to be capable of functioning in conformity with th
