SIST EN IEC 61109:2025

Insulators for overhead lines - Composite suspension and tension insulators for a.c. systems with a nominal voltage greater than 1 000 V - Definitions, test methods and acceptance criteria (IEC 61109:2025)

IEC 61109:2025 applies to composite insulators for overhead lines consisting of a load-bearing cylindrical insulating solid core consisting of fibres - usually glass - in a resin-based matrix, a housing (surrounding the insulating core) made of polymeric material and metal end fittings permanently attached to the insulating core. Composite insulators covered by this document are intended for use as suspension/tension line insulators, but these insulators could occasionally be subjected to compression or bending, for example when used as interphase-spacers. Guidance on such loads is outlined in Annex C.
The object of this document is to:
- define the terms used,
- specify test methods,
- specify acceptance criteria.
This third edition cancels and replaces the second edition published in 2008. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
- extension of this document to apply both to AC and DC systems;
- modifications of Clause 3, Terms, definitions and abbreviations;
- removal of Clause 7, Hybrid insulators, from this document;
- modifications of tests procedures recently included in IEC 62217 (hydrophobicity transfer test, stress corrosion, water diffusion test on the core with housing);
- modifications on environmental conditions;
- modifications on classification of tests and include the relevance of the interfaces;
- clarification and modification of the parameters determining the need to repeat design and type tests;
- revision of Table 1;
- revision of electrical type tests;
- revision of re-testing procedure of sample test;
- addition of a new Annex D on electric field control for AC;
- addition of a new Annex E on typical sketch for composite insulators assembly;
- addition of a new Annex F on mechanical evaluation of the adhesion between core and housing;
- addition of a new Annex G on applicability of design- and type tests for DC applications.

Isolatoren für Freileitungen - Verbund-Hänge- und -Abspannisolatoren für Wechselstromsysteme mit einer Nennspannung über 1 000 V - Begriffe, Prüfverfahren und Annahmekriterien (IEC 61109:2025)

Isolateurs pour lignes aériennes - Isolateurs composites de suspension et d'ancrage destinés aux systèmes à courant alternatif de tension nominale supérieure à 1 000 v - Définitions, méthodes d'essai et critères d'acceptation (IEC 61109:2025)

L'IEC 61109:2025 s'applique aux isolateurs composites pour lignes aériennes qui sont constitués d'un noyau isolant plein cylindrique réalisé en fibres - généralement de verre - qui supporte les charges. Ces isolateurs possèdent une matrice en résine, un revêtement (recouvrant le noyau isolant) en matériau élastomère et des armatures d'extrémité métalliques fixées au noyau isolant. Les isolateurs composites couverts par le présent document sont destinés à être utilisés pour la suspension ou l'ancrage de lignes, mais ces isolateurs peuvent parfois être sollicités en compression ou en flexion, par exemple lorsqu'ils sont utilisés comme entretoises interphases. L'Annexe C fournit des recommandations pour ces types de charges.
L'objet du présent document est de:
- définir les termes utilisés;
- spécifier les méthodes d'essai;
- spécifier les critères acceptation.
Cette troisième édition annule et remplace la deuxième édition parue en 2008. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- élargissement du présent document pour inclure les systèmes à courant alternatif et à courant continu;
- modifications de l'Article 3, Termes, définitions et abréviations;
- suppression de l'Article 7, Isolateurs hybrides, dans le présent document;
- modifications des procédures d'essai récemment incluses dans l'IEC 62217 (essai de transfert d'hydrophobie, essai de corrosion sous contrainte, essai de pénétration d'eau - sur le noyau avec le revêtement);
- modifications des conditions d'environnement;
- modifications de la classification des essais et ajout de la pertinence des interfaces;
- clarification et modification des paramètres qui déterminent la nécessité de répéter les essais de conception et de type;
- révision du Tableau 1;
- révision des essais électriques de type;
- révision de la procédure de contre-épreuve de l'essai sur prélèvement;
- ajout d'une nouvelle Annexe D sur la maîtrise des champs électriques pour les applications en courant alternatif;
- ajout d'une nouvelle Annexe E sur les croquis types pour l'assemblage des isolateurs composites;
- ajout d'une nouvelle Annexe F sur l'évaluation mécanique de l'adhérence entre le noyau et le revêtement;
- ajout d'une nouvelle Annexe G sur l'applicabilité des essais de conception et de type pour les applications en courant continu.

Izolatorji za nadzemne vode - Sestavljeni obesni nosilni in strižni zatezni izolatorji za izmenične sisteme z nazivno napetostjo nad 1 000 V - Definicije, preskusne metode in prevzemna merila (IEC 61109:2025)

General Information

• Status: Not Published
• Public Enquiry End Date: 28-Feb-2024
• ICS: 29.080.10 - Insulators
• ICS: 29.240.20 - Power transmission and distribution lines
• Technical Committee: IZL - Insulators
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 24-Apr-2025
• Due Date: 29-Jun-2025
• Ref Project: EN IEC 61109:2025 - Insulators for overhead lines - Composite suspension and tension insulators for a.c. systems with a nominal voltage greater than 1 000 V - Definitions, test methods and acceptance criteria

Relations

• Revised: SIST EN 61109:2008 - Insulators for overhead lines - Composite suspension and tension insulators for a.c. systems with a nominal voltage greater than 1 000 V - Definitions, test methods and acceptance criteria (IEC 61109:2008)
• Effective Date: 26-Jul-2021

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN IEC 61109:2024
01-februar-2024
Izolatorji za nadzemne vode - Sestavljeni obesni in strižni izolatorji za izmenične
sisteme z nazivno napetostjo nad 1 000 V - Definicije, preskusne metode in
prevzemna merila
Insulators for overhead lines - Composite suspension and tension insulators for a.c.
systems with a nominal voltage greater than 1 000 V - Definitions, test methods and
acceptance criteria
Isolatoren für Freileitungen - Verbund-Hänge- und -Abspannisolatoren für
Wechselstromsysteme mit einer Nennspannung über 1 000 V - Begriffe, Prüfverfahren
und Annahmekriterien
Isolateurs pour lignes aériennes - Isolateurs composites de suspension et d'ancrage
destinés aux systèmes à courant alternatif de tension nominale supérieure à 1 000 v -
Définitions, méthodes d'essai et critères d'acceptation
Ta slovenski standard je istoveten z: prEN IEC 61109:2023
ICS:
29.080.10 Izolatorji Insulators
29.240.20 Daljnovodi Power transmission and
distribution lines
oSIST prEN IEC 61109:2024 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN IEC 61109:2024
oSIST prEN IEC 61109:2024
36/590/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61109 ED3
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2023-12-08 2024-03-01
SUPERSEDES DOCUMENTS:
36/583/RR
IEC TC 36 : INSULATORS
SECRETARIAT: SECRETARY:
Sweden Mr Dan Windmar
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:

TC 11
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:
Insulators for overhead lines - Composite suspension and tension insulators for a.c. systems
with a nominal voltage greater than 1 000 V - Definitions, test methods and acceptance criteria

PROPOSED STABILITY DATE: 2027
NOTE FROM TC/SC OFFICERS:
download this 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 61109:2024
IEC CDV 61109 © IEC 2023 2 36/590/CDV

1 CONTENTS
2 CONTENTS . 2
3 FOREWORD. 5
4 INTRODUCTION . 7
5 1 Scope and object . 8
6 2 Normative references . 8
7 3 Terms, definitions and abbreviations . 8
8 3.1 Terms and definitions . 9
9 3.22 Abbreviations . 12
10 4 Identification . 12
11 5 Environmental conditions . 12
12 6 Transport, storage and installation . 13
13 7 Tolerances . 13
14 8 Classification of tests . 14
15 8.1 Design tests . 14
16 8.2 Type tests . 14
17 8.3 Sample tests . 15
18 8.4 Routine tests . 15
19 9 Design tests . 18
20 9.1 General . 18
21 9.2 Test specimens for IEC 62217 . 18
22 9.2.1 Tests on interfaces and connections of end fittings . 18
23 9.2.2 Tracking and erosion test . 19
24 9.2.3 Tests on core material . 19
25 9.2.4 Tests on core with housing . 19
26 9.3 Product specific pre-stressing for tests on interfaces and connections of end
27 fittings as in IEC 62217 . 19
28 9.3.1 Sudden load release . 19
29 9.3.2 Thermal-mechanical pre-stress . 19
30 9.4 Assembled core load-time tests . 20
31 9.4.1 Test specimens . 20
32 9.4.2 Mechanical load test . 20
33 10 Type tests . 21
34 10.1 Electrical tests on string insulator units . 21
35 10.2 Damage limit proof test and test of the tightness of the interface between
36 end fittings and insulator housing . 22
37 10.2.1 Test specimens . 22
38 10.2.2 Performance of the test . 23
39 10.2.3 Evaluation of the test . 23
40 11 Sample tests . 23
41 11.1 General rules . 23
42 11.2 Verification of dimensions (E1 + E2) . 25
43 11.3 Verification of the end fittings (E2) . 25
44 11.4 Verification of tightness of the interface between end fittings and insulator
45 housing (E2) and of the specified mechanical load, SML (E1) . 25
46 11.5 Galvanizing test (E2) . 26
47 11.6 Minimum sheath thickness. (E1) . 26
48 11.7 Re-testing procedure . 27
49 12 Routine tests . 28

oSIST prEN IEC 61109:2024
IEC CDV 61109 © IEC 2023 3 36/590/CDV

50 12.1 Mechanical routine test . 28
51 12.2 Visual examination . 28
52 Annex A (informative) Principles of the damage limit, load coordination and testing for
53 composite suspension and tension insulators . 29
54 A.1 Introductory remark . 29
55 A.2 Load-time behaviour and the damage limit . 29
56 A.3 Service load coordination . 30
57 A.4 Verification tests . 34
58 Annex B (informative) Example of two possible devices for sudden release of load . 35
59 B.1 Device 1 (Figure B.1) . 35
60 B.2 Device 2 (Figure B.2) . 35
61 Annex C (informative) Guidance on non-standard mechanical stresses and dynamic
62 mechanical loading of composite insulators . 37
63 C.1 Introductory remark . 37
64 C.2 Torsion loads . 37
65 C.3 Compressive (buckling) loads . 37
66 C.4 Bending loads. 38
67 C.5 Dynamic mechanical loads . 38
68 C.6 Limits . 38
69 Annex D (informative) Electric field control for AC . 39
70 Annex E (informative) Typical sketches for composite insulator assemblies . 41
71 Annex F (informative) Mechanical evaluation of the adhesion between core and
72 housing . 42
73 F.1 Introduction . 42
74 F.2 Method A: Pull-off test . 42
75 F.2.1 Specimens . 42
76 F.2.2 Procedure . 43
77 F.3 Method B: Peel test . 44
78 F.3.1 Specimens . 44
79 F.3.2 Procedure . 45
80 F.4 Method C: Shear test . 45
81 F.4.1 Specimens . 45
82 F.4.2 Procedure . 46
83 Annex G (informative) Applicability of design- and type tests for DC applications . 47
oSIST prEN IEC 61109:2024
IEC CDV 61109 © IEC 2023 4 36/590/CDV

85 Figure 1 − Thermal-mechanical pre-stressing . 20
86 Figure 3 − Method of re-testing at different stages . 27
87 Figure A.1 − Load-time strength and damage limit of a core assembled with fittings . 30
88 Figure A.2 – Graphical representation of the relationship of the damage limit to the
89 mechanical characteristics and service loads of an insulator with a 16 mm diameter
90 core 31
91 Figure A.3 – Applied specific force relationship example 1 . 32
92 Figure A.4 – Applied specific force relationship example 2 . 33
93 Figure A.5 – Test loads . 34
94 Figure B.1 − Example of possible device 1 for sudden release of load . 35
95 Figure B.2 − Example of possible device 2 for sudden release of load . 36
96 Figure C.1 – Example of compression loads in V-string assemblies . 38
97 Figure E.1.- Interface description for insulator with housing made by modular assembly
98 and external sealant . 41
99 Figure E.2.- Interface description for insulator with housing made by injection molding
100 and overmolded end fitting . 41
101 Figure F.1 − Example for type of housing separation . 42
102 Figure F.2 − Example of test object for pull-off test and application clamping and force
103 43
104 Figure F.3 − Relevant dimensions for the calculation of the area of the pull-off section
105 44
106 Figure
...