1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULNational Differences ForUL 60079-28Explosive Atmospheres Part 28: Protection of Equipment and Transmission Systems UsingOptical RadiationUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODU
2、CTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULNational Differences ForUL 60079-28Explosive Atmospheres Part 28: Protection of Equipment and Transmission Systems Using OpticalRadiationSecond EditionEdition Date: SEPTEMBER 15, 2017Adoption of IEC 60079-28, Edition 2.0 (2015-05), Explosive Atmospheres
3、 - Part 28: Protection ofEquipment and Transmission Systems Using Optical Radiation, as a new IEC-based ULstandard, UL 60079-28 with US National Differences.This document provides a single listing of the National Differences included in the UL adoption ofthe corresponding IEC standard.All rights res
4、erved. No part of this publication may be reproduced, stored in a retrieval system, ortransmitted in any form by any means, electronic, mechanical photocopying, recording, or otherwisewithout prior permission of UL.UL provides this standards document as is without warranty of any kind, either expres
5、sed or implied,including but not limited to, the implied warranties of merchantability or fitness for any purpose.In no event will UL be liable for any special, incidental, consequential, indirect or similar damages,including loss of profits, lost savings, loss of data, or any other damages arising
6、out of the use of or theinability to use this standards document, even if UL or an authorized UL representative has been advisedof the possibility of such damage. In no event shall ULs liability for any damage ever exceed the pricepaid for this standards document, regardless of the form of the claim
7、.Users of the electronic versions of ULs Standards for Safety agree to defend, indemnify, and hold ULharmless from and against any loss, expense, liability, damage, claim, or judgment (including reasonableattorneys fees) resulting from any error or deviation introduced while purchaser is storing an
8、electronicStandard on the purchasers computer system.Copyright 2017 Underwriters Laboratories Inc.SEPTEMBER 15, 2017NATIONAL DIFFERENCES FOR UL 60079-282UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULPrefaceThis document provides a single lis
9、ting of the technical National Differences included in the UL adoptionof the corresponding IEC standard.In its IEC-based standards, UL uses the notations indicated below to identify national difference type, andthese types are additionally noted in this document. The standard may not use all types o
10、f thesedeviations.D1 - These are deviations which are based on basic safety principles and requirements, elimination ofwhich would compromise safety for U.S. consumers and users of products.D2 - These are deviations based on safety practices. These are deviations for IEC requirements that maybe acce
11、ptable, but adopting the IEC requirements would require considerable retesting or redesign on themanufacturers part.DC - These are deviations based on the component standards and will not be deleted until a particularcomponent standard is harmonized with the IEC component standard.DE - These are dev
12、iations based on editorial comments or corrections.DR - These are deviations based on the national regulatory requirements.Each national difference contains a description of what the national difference entails. Typically one of thefollowing words is used to explain how the text of the national diff
13、erence is to be applied to the base IECtext:Addition / Add - An addition entails adding a complete new numbered clause, subclause, table, figure,or annex. Addition is not meant to include adding select words to the base IEC text.Deletion / Delete - A deletion entails complete deletion of an entire n
14、umbered clause, subclause, table,figure, or annex without any replacement text.Modification / Modify - A modification is an altering of the existing base IEC text such as the addition,replacement or deletion of certain words or the replacement of an entire clause, subclause, table, figure,or annex o
15、f the base IEC text.SEPTEMBER 15, 2017 NATIONAL DIFFERENCES FOR UL 60079-28 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULNational Differences1DV.1 DR Modification of Clause 1 to replace with the following:1DV.1.1 DR This part of IEC 60079
16、standard specifies the requirements, testing andmarking of equipment emitting optical radiation intended for use in explosiveatmospheres. It also covers equipment located outside the explosive atmosphere orprotected by a Type of Protection listed in IEC UL 60079-0, but which generates opticalradiati
17、on that is intended to enter an explosive atmosphere. It covers Groups I, II and III,and EPLs Ga, Gb, Gc, Da, Db, Dc, Ma and Mb.1.2 This standard contains requirements for optical radiation in the wavelength range from380 nm to 10 m. It covers the following ignition mechanisms:Optical radiation is a
18、bsorbed by surfaces or particles, causing them to heat up, and undercertain circumstances this may allow them to attain a temperature which will ignite asurrounding explosive atmosphere.In rare special cases, direct laser induced breakdown of the gas at the focus of a strongbeam, producing plasma an
19、d a shock wave both eventually acting as ignition source.These processes can be supported by a solid material close to the breakdown point.NOTE 1 See a) and d) of the introduction.1.3 This standard does not cover ignition by ultraviolet radiation and by absorption of theradiation in the explosive mi
20、xture itself. Explosive absorbers or absorbers that containtheir own oxidizer as well as catalytic absorbers are also outside the scope of thisstandard.1.4 This standard specifies requirements for equipment intended for use underatmospheric conditions.1DV.1.5 DR Annex F outlines the application of t
21、his standard for equipment andtransmission systems using optical radiation in areas classified using the Divisionmethod.1DV.1.6 DR This standard supplements and modifies the general requirements of IEC UL60079-0. Where a requirement of this standard conflicts with a requirement of IEC UL60079-0, the
22、 requirement of this standard takes precedence.1DV.1.7 DR Where references are made to other IEC 60079 standards, the referencedrequirements found in these standards apply as modified by any applicable U.S. NationalDifferences.SEPTEMBER 15, 2017NATIONAL DIFFERENCES FOR UL 60079-284UL COPYRIGHTED MAT
23、ERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL1DV.1.8 DR This standard applies to optical fibre equipment and optical equipment,including LED and laser equipment, with the exception of the equipment detailed below:NOTE 2 Where certifications for equipment and
24、 transmission systems using optical radiation meet one of the fiveexceptions below, and do not reference UL 60079-28, the certificate or other supporting documentation may havethe following statement, modified appropriately:“The output of the optical radiation source with respect to explosion protec
25、tion meets Exception X)from the scope of UL 60079-28”.The reference to “Exception X)” above is to be replaced by the actual number of the Exception that applies fromthe scope of UL 60079-28, e.g. “Exception 1)”, “Exception 2)”, “Exception 3)”, “Exception 4)” or “Exception 5)”.1) Non-array divergent
26、LEDs used for example to show equipment status or backlightfunction.1DV.1.8.1 D22) All luminaires (fixed, portable or transportable), hand lights and caplights; intended tobe supplied by mains (with or without galvanic isolation) or powered by batteries with anycontinuous divergent light source, inc
27、luding LEDs (for all EPLs).: with continuous divergent light sources (for all EPLs), with LED light sources (for EPL Gc or Dc only).NOTE 2 Continuous divergent LED light sources for other than EPL Gc or Dc are not excluded from the standarddue to the uncertainty of potential ignition concerns regard
28、ing high irradiance.1DV.1.9 DR Optical radiation sources for EPL Gc and Dc applications which comply withClass I limits in accordance with the US Code of Federal Regulations, 21 CFR Part 1040.NOTE 3 The referenced Class 1 or Class I limits are those that involve emission limits below 15 mW measured
29、ata distance from the optical radiation source in accordance with IEC 60825-1 or the US Code of FederalRegulations, 21 CFR Part 1040, respectively, with this measured distance reflected in the Ex application. TheseClass I limits are based on normal operating and single fault conditions, as opposed t
30、o Class I limits which areonly based on normal operating conditions.4) Single or multiple optical fibre cables not part of optical fibre equipment if the cables: comply with the relevant industrial standards, along with additional protectivemeans, e.g. robust cabling, conduit or raceway (for EPL Gb,
31、 Db, Mb, Gc or Dc), comply with the relevant industrial standards (for EPL Gc or Dc).5) Enclosed equipment involving an enclosure that fully contains the optical radiation andthat complies with a suitable type of protection as required by the involved EPL, with theenclosure complying with one of the
32、 following conditions: An enclosure for which an ignition due to optical radiation in combination withabsorbers inside the enclosure would be acceptable such as flameproof denclosures (IEC UL 60079-1), orSEPTEMBER 15, 2017 NATIONAL DIFFERENCES FOR UL 60079-28 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED
33、FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL An enclosure for which protection regarding ingress of an explosive gasatmosphere is provided, such as pressurized p enclosures (IEC UL 60079-2),restricted breathing “nR” enclosure (IEC UL 60079-15), or An enclosure for which protect
34、ion regarding ingress of an explosive dustatmosphere is provided, such as dust protection t enclosures (IEC UL 60079-31), or An enclosure for which protection regarding ingress of absorbers is provided(such as IP 6X enclosures) and where no internal absorbers are to be expected.NOTE 4 For these scop
35、e exclusions based on enclosure constructions, it is anticipated that the enclosures arenot opened in the explosive atmosphere, so that ingress is protected.2DV DR Modification of Clause 2 to replace with the following:IEC 60050, International Electrotechnical VocabularyIEC 60079-0, Explosive atmosp
36、heres Part 0: Equipment General requirementsIEC 60079-1, Explosive atmospheres Part 1: Equipment protection by flameproof enclosures dIEC 60079-11, Explosive atmospheres Part 11: Equipment protection by intrinsic safety iIEC 60079-15, Explosive atmospheres Part 15: Equipment protection by type of pr
37、otection nIEC 60825-2, Safety of laser products Part 2: Safety of optical fibre communication systems(OFCS)NFPA 70, National Electrical CodeUL 1651 Optical Fiber CableUL 60079-0 Explosive atmospheres Part 0: Equipment General requirementsUL 60079-1 Explosive atmospheres Part 1: Equipment protection
38、by flameproof enclosures dUL 60079-11 Explosive atmospheres Part 11: Equipment protection by intrinsic safety iUL 60079-15 Explosive atmospheres Part 15: Equipment protection by type of protection n5.3.2DV.1 DR Modification of Clause 5.3.2 to replace with the following:The optical fibre or cable pro
39、tects the release of optical radiation into the atmosphereduring normal operating conditions. For EPL Gb, Db or Mb protected optical fibre cablesshall be used provided by additional armouring, conduit, cable tray, or raceway. For opticalfibres or cables, that exit the end-equipment enclosure, a pull
40、 test shall be performedaccording to IEC 60079-11.Gb, Gc, Db and Dc equipment shall utilize single or multiple optical fiber cable (asdescribed in Article 770 and other applicable parts of the National Electrical Code, NFPA70) that complies with UL 1651.SEPTEMBER 15, 2017NATIONAL DIFFERENCES FOR UL
41、60079-286UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULInternal or external cables can be terminated/ spliced from one fibre (from a cable) toanother fibre (in a new cable) by using dedicated coupler or joining kits giving a fixedtermination
42、. For external termination/splicing, the cable connection shall provideequivalent mechanical strength to that of the cable. The procedure to perform fieldconnections shall be detailed in the instructions.NOTE 1 This can be achieved by using mechanical clamping or snap connection.For EPL Gc or Dc opt
43、ical fibre or cables and internal pluggable factory connections thatcomply with the applicable industrial standard are suitable. External optical fibre or cablefield connections shall comply with the external plug and socket outlet requirements fromIEC 60079-0 suitable for the EPL.For EPL Gb, Db or
44、Mb, optical fibre or cables connected via internal pluggable factoryconnections shall comply with the pluggable connections requirements from IEC 60079-15.External optical fibre or cable field connections shall comply with the external plug andsocket outlet requirements from IEC 60079-0 for the requ
45、ired EPL.NOTE 2 Typical examples are connections in split-boxes.NOTE 3 Optical fibre or cable alone is not Ex equipment.5.4DV.1 DR Modification of Clause 5.4 Note to replace with the following:NOTE Ignition delay times are only identified for Group I, Group IIA temperature class T1and Group IIA temp
46、erature class T2 in Figure 1. Therefore, type of protection, op sh,isnot permitted ignition delay times for other Group IIA applications or for any Group IIB andGroup IIC applications necessitate additional testing and documentation to establishsuitable times.5.4DV.2 DE Modification of Clause 5.4, f
47、ifth paragraph to replace with the following:The interlock cut-off shall be required to perform according to the requirements defined bythe risk analysis. The methods given in appropriate standards (e.g. IEC 61508, IEC 61511,ISA-84.00.01, Parts 1-3) may be used to analyse equipment performance for t
48、he appropriatesafety level. According to Table 1 the shutdown system is required to operate safely withone fault.7DV DR Modification of Clause 7 to replace with the following:The equipment using optical radiation shall include all markings required by the otherapplicable equipment protection techniq
49、ues, if any, (such as flameproof enclosures, “d”,and intrinsically safe apparatus, “i”). Electrical equipment, parts of electrical equipment,and Ex components emitting optical radiation and protected by the types of protectionspecified in this standard shall be marked in accordance with IEC 60079-0 UL 60079-0, withthe following additional marking:a) the symbol for the type of protection used:“op is”: for inherently safe optical radiation;“op pr”: for protected optical radiation;SEPTEMBER 15, 2017 NATIONAL DIFFERENCES FOR U
