FprEN IEC 61869-20:2024
(Main)Instrument transformers - Part 20: Safety requirements of instrument transformers for high voltage applications
Instrument transformers - Part 20: Safety requirements of instrument transformers for high voltage applications
Sicherheitsanforderungen von Messwandlern für Hochspannungsanwendungen
Transformateurs de mesure - Partie 20: Exigences de sécurité des transformateurs de mesure pour applications à haute tension
Instrumentni transformatorji - 20. del: Varnostne zahteve instrumentalnih transformatorjev za visokonapetostne aplikacije
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN IEC 61869-20:2024
01-april-2024
IEC 61869-20: Varnostne zahteve instrumentalnih transformatorjev za
visokonapetostne aplikacije
IEC 61869-20: Safety requirements of Instrument Transformers for High Voltage
applications
Ta slovenski standard je istoveten z: prEN IEC 61869-20:2024
ICS:
17.220.20 Merjenje električnih in Measurement of electrical
magnetnih veličin and magnetic quantities
oSIST prEN IEC 61869-20:2024 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
oSIST prEN IEC 61869-20:2024
oSIST prEN IEC 61869-20:2024
38/786/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61869-20 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2024-02-09 2024-05-03
SUPERSEDES DOCUMENTS:
38/725/NP, 38/771A/RVN
IEC TC 38 : INSTRUMENT TRANSFORMERS
SECRETARIAT: SECRETARY:
Italy Mr Filippo Frugoni
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
TC 64
Other TC/SCs are requested to indicate their interest, if any, in this
CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which they
are aware and to provide supporting documentation.
Recipients of this document are invited to submit, with their comments, notification of any relevant “In Some Countries”
clauses to be included should this proposal proceed. Recipients are reminded that the CDV stage is the final stage for
submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).
TITLE:
IEC 61869-20: Safety requirements of Instrument Transformers for High Voltage applications
PROPOSED STABILITY DATE: 2028
NOTE FROM TC/SC OFFICERS:
electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.
You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without
permission in writing from IEC.
oSIST prEN IEC 61869-20:2024
38/786/CDV – 2 – IEC CDV 61869-20 © IEC:2023
1 CONTENTS
3 FOREWORD . 4
4 1 Scope . 6
5 2 Normative references . 6
6 3 Terms and definitions . 6
7 4 Protection against electric shock . 7
8 4.1 General . 7
9 4.2 Earthing of housing, terminals and connection to carrier-frequency
10 accessory . 7
11 4.2.1 General . 7
12 4.2.2 Earthing of HV CTs . 7
13 4.2.3 Earthing of HV VTs . 9
14 4.3 Access to secondary terminals . 12
15 4.3.1 General . 12
16 4.3.2 Indoor instrument transformers . 12
17 4.3.3 Outdoor instrument transformers . 12
18 4.3.4 Protection of equipment against mechanical impact under normal
19 service conditions . 13
20 4.4 Risk of open CTs and shorted VTs secondary terminals . 13
21 4.4.1 General . 13
22 4.4.2 Protections against the risk of open CTs secondary terminals . 13
23 4.4.3 Protections against the risk of shorted VTs secondary terminals . 13
24 5 Protection against thermal and chemical hazards . 13
25 5.1 General . 13
26 5.2 Risk of fire . 13
27 5.3 Risk of internal arc . 14
28 5.4 Risk of leakage of oil or release of gases . 14
29 6 Protection against mechanical hazards . 14
30 6.1 General . 14
31 6.2 Hazards during mounting and dismounting . 14
32 Bibliography . 15
34 Figure 1 – Earthing of a CT with one secondary circuit . 8
35 Figure 2 – Earthing of a CT with one secondary circuit having a tap . 8
36 Figure 3 – Earthing of a CT with two secondary circuits . 8
37 Figure 4 – Earthing terminal connected to the steel support structure . 9
38 Figure 5 – Earthing terminal connected to earth via an earthing conductor . 9
39 Figure 6 – Earthing of an earthed VT with one secondary circuit . 10
40 Figure 7 – Earthing of an unearthed VT with one secondary circuit . 10
41 Figure 8 – Earthing of an earthed VT with two secondary circuits . 11
42 Figure 9 – Earthing of an earthed VT with a multi-tap secondary circuit . 11
43 Figure 10 – Earthing terminal connected to the steel support structure . 11
44 Figure 11 – Earthing terminal connected to earth via an earthing conductor . 12
oSIST prEN IEC 61869-20:2024
IEC CDV 61869-20 © IEC:2023 – 3 – 38/786/CDV
46 Table 1 – Fire hazard of electrotechnical products . 14
oSIST prEN IEC 61869-20:2024
38/786/CDV – 4 – IEC CDV 61869-20 © IEC:2023
50 INTERNATIONAL ELECTROTECHNICAL COMMISSION
51 ____________
53 INSTRUMENT TRANSFORMERS
54 Part 20: Safety requirements of instrument transformers for high voltage
55 applications
57 FOREWORD
58 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
59 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
60 co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
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66 Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
67 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
68 consensus of opinion on the relevant subjects since each technical committee has representation from all
69 interested IEC National Committees.
70 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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74 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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85 Publications.
86 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
87 indispensable for the correct application of this publication.
88 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
89 rights. IEC shall not be held responsible for identifying any or all such patent rights.
90 IEC 61869-20 has been prepared by committee 38: Instrument Transformers. It is an
91 International Standard.
92 The text of this International Standard is based on the following documents:
Draft Report on voting
XX/XX/FDIS XX/XX/RVD
94 Full information on the voting for its approval can be found in the report on voting indicated in
95 the above table.
96 The language used for the development of this International Standard is English.
97 This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
98 accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
99 at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
100 described in greater detail at www.iec.ch/standardsdev/publications.
oSIST prEN IEC 61869-20:2024
IEC CDV 61869-20 © IEC:2023 – 5 – 38/786/CDV
101 The committee has decided that the contents of this document will remain unchanged until the
102 stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
103 the specific document. At this date, the document will be
104 • reconfirmed,
105 • withdrawn,
106 • replaced by a revised edition, or
107 • amended.
oSIST prEN IEC 61869-20:2024
38/786/CDV – 6 – IEC CDV 61869-20 © IEC:2023
110 INSTRUMENT TRANSFORMERS
111 Part 20: Safety requirements of instrument transformers for high voltage
112 applications
116 1 Scope
117 This part of IEC 61869 specifies the requirements for the safe design and operation, and tests
118 for the safety of instrument transformers whose highest voltage for equipment is higher than 1
119 kV AC or 1,5 kV DC.
120 Low Power Instrument Transformers are not covered by this document.
121 NOTE The possibility to include the additional safety requirements, specific for Low Power Instrument Transformers,
122 is currently under consideration.
123 2 Normative references
124 The following documents are referred to in the text in such a way that some or all of their content
125 constitutes requirements of this document. For dated references, only the edition cited applies.
126 For undated references, the latest edition of the referenced document (including any
127 amendments) applies.
128 IEC 61869-1, Instrument transformers - Part 1: General requirements
129 IEC 61869-99, Instrument transformers - Part 99: Glossary
130 IEC 60947-2, Low-voltage switchgear and controlgear - Part 2: Circuit-breakers
131 IEC 60947-7-1, Low-voltage switchgear and controlgear - Part 7-1: Ancillary equipment -
132 Terminal blocks for copper conductors
133 IEC 60529, Degrees of protection provided by enclosures (IP Code)
134 IEC 62262, Degrees of protection provided by enclosures for electrical equipment against
135 external mechanical impacts (IK code)
136 IEC 60695-1-10, Fire hazard testing - Part 1-10: Guidance for assessing the fire hazard of
137 electrotechnical products - General guidelines
138 IEC 60695-1-11, Fire hazard testing - Part 1-11: Guidance for assessing the fire hazard of
139 electrotechnical products - Fire hazard assessment
...
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