IEC TS 60079-47:2021

IEC TS 60079-47 ®
Edition 1.0 2021-02
TECHNICAL
SPECIFICATION
Explosive atmospheres –
Part 47: Equipment protection by 2-wire intrinsically safe Ethernet concept
(2-WISE)
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IEC TS 60079-47 ®
Edition 1.0 2021-02
TECHNICAL
SPECIFICATION
Explosive atmospheres –
Part 47: Equipment protection by 2-wire intrinsically safe Ethernet concept

(2-WISE)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.260.20 ISBN 978-2-8322-9317-1

– 2 – IEC TS 60079-47:2021  IEC 2021
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Requirements for 2-WISE devices . 6
4.1 General . 6
4.2 2-WISE power source ports . 7
4.3 2-WISE power load ports and 2-WISE auxiliary device ports . 7
4.4 2-WISE communication only ports . 8
4.5 Simple apparatus . 8
5 Requirements for 2-WISE systems . 8
5.1 General . 8
5.2 Wiring systems . 9
5.3 Powered 2-WISE systems . 9
5.4 Communication only 2-WISE systems . 9
5.5 Descriptive system document . 10
6 Schedule drawings and instructions for 2-WISE devices . 10
7 Marking . 11
7.1 General . 11
7.2 Examples of marking . 11
Bibliography . 14

Figure 1 – DC-powered 2-WISE system . 9
Figure 2 – Communication only 2-WISE system . 10

Table 1 – Intrinsically safe parameters for 2-WISE Power load ports and auxiliary
device ports . 7
Table 2 – Intrinsically safe parameters for 2-WISE communication only ports . 8

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
EXPLOSIVE ATMOSPHERES –
Part 47: Equipment protection by 2-wire intrinsically
safe Ethernet concept (2-WISE)

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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The main task of IEC technical committees is to prepare International Standards. In exceptional
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when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide whether
they can be transformed into International Standards.
IEC TS 60079-47, which is a technical specification, has been prepared by subcommittee 31G:
Intrinsically safe apparatus, of IEC technical committee 31: Equipment for explosive
atmospheres.
– 4 – IEC TS 60079-47:2021  IEC 2021
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
31G/323/DTS 31G/334/RVC
Full information on the voting for the approval of this technical specification can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60079 series, published under the general title Explosive
atmospheres, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
EXPLOSIVE ATMOSPHERES –
Part 47: Equipment protection by 2-wire intrinsically
safe Ethernet concept (2-WISE)

1 Scope
This part of IEC 60079, which is a technical specification, specifies requirements for the
construction, marking and documenting of apparatus, systems and installations for use with the
2-Wire Intrinsically Safe Ethernet concept (2-WISE), such as the physical layer specification for
2-Wire Ethernet 10BASE-T1L as defined in IEEE 802.3cg.
2-WISE is a concept for an advanced physical layer (APL), designed to simplify the examination
process for intrinsic safety parameters of components and cabling within APL segments. This
is achieved by defining universal intrinsic safety parameter limits for APL ports, according to
the specific hazardous area requirements and listing a concise set of rules for the segment
setup.
The requirements for construction and installation of 2-WISE devices and systems are included
in IEC 60079-11, IEC 60079-14, and IEC 60079-25, except as modified by this document. Parts
of a 2-WISE device can be protected by any Type of Protection listed in IEC 60079-0
appropriate to the EPL for the intended hazardous area. In these circumstances, the
requirements of this technical specification apply only to intrinsically safe circuits of the
apparatus.
Where a requirement of this document conflicts with a requirement of IEC 60079-0,
IEC 60079-11, IEC 60079-14 or IEC 60079-25, the requirements of this document take
precedence.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 60079-0, Explosive atmospheres - Part 0: Equipment - General requirements
IEC 60079-11, Explosive atmospheres - Part 11: Equipment protection by intrinsic safety "i"
IEC 60079-14, Explosive atmospheres - Part 14: Electrical installations design, selection and
erection
IEC 60079-25, Explosive atmospheres - Part 25: Intrinsically safe electrical systems
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60079-0,
IEC 60079-11, IEC 60079-14, IEC 60079-25 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp

– 6 – IEC TS 60079-47:2021  IEC 2021
3.1
10BASE-T1L
physical layer standard for 10 Mb/s Ethernet communication over a single balanced twisted-
pair copper cabling with optional provision of power
Note 1 to entry: This is standardized in IEEE 802.3cg.
3.2
Advanced Physical Layer
APL
physical layer based on 10BASE-T1L
3.3
2-Wire Intrinsically Safe Ethernet
2-WISE
intrinsically safe electrical d
...