IEC TR 61916:2017

Electrical accessories - Harmonization of general rules

IEC TR 61916:2017(E) provides guidance on requirements and tests for subjects applicable to electrical accessories that are within the scope of IEC TC 23 and its subcommittees.
This fourth edition cancels and replaces the third edition published in 2014 and constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) clarification of the introduction and the scope;
b) clarification of subclause 6.3;
c) modification of Clause 7;
d) modification of Clause 10;
e) addition of Annex B for temperature selection for GWEPT.

General Information

• Status: Published
• Publication Date: 27-Mar-2017
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 01.040.17 - Metrology and measurement. Physical phenomena (Vocabularies)
• ICS: 17.220.01 - Electricity. Magnetism. General aspects
• ICS: 29.020 - Electrical engineering in general
• ICS: 29.120.01 - Electrical accessories in general
• Technical Committee: TC 23 - Electrical accessories
• Drafting Committee: MT 11 - TC 23/MT 11
• Current Stage: PPUB - Publication issued
• Start Date: 10-Apr-2017
• Completion Date: 28-Mar-2017

Relations

• Revises: IEC TR 61916:2014 - Electrical accessories - Harmonization of general rules
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC TR 61916 ®
Edition 4.0 2017-03
TECHNICAL
REPORT
colour
inside
Electrical accessories – Harmonization of general rules
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IEC TR 61916 ®
Edition 4.0 2017-03
TECHNICAL
REPORT
colour
inside
Electrical accessories – Harmonization of general rules

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.120.01 ISBN 978-2-8322-4117-2

– 2 – IEC TR 61916:2017 © IEC 2017
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 General requirements . 8
4.1 General . 8
4.2 Standard conditions for operation in service . 8
4.2.1 Ambient temperature . 8
4.2.2 Altitude . 9
4.2.3 Maximum relative humidity at 40 °C . 9
4.2.4 External magnetic field . 9
4.2.5 Accessory orientation . 9
4.3 Ambient air temperature range for testing . 9
5 Resistance to heat . 9
5.1 General . 9
5.2 Requirements . 9
5.3 Tests . 10
6 Screws, current-carrying parts and connections (electrical and mechanical) . 11
6.1 General . 11
6.2 Types of screw . 11
6.2.1 Thread-forming screw . 11
6.2.2 Thread-cutting screw . 11
6.3 Requirements . 12
6.4 Tests . 14
7 Resistance to abnormal heat and to fire . 15
7.1 General . 15
7.2 Requirements . 15
7.3 Glow-wire flammability test for end-products, IEC 60695-2-11 . 16
7.3.1 Purpose and principle . 16
7.3.2 Test method . 17
7.3.3 Relevance of test data . 17
8 Resistance of insulating materials to tracking . 18
8.1 General . 18
8.2 Requirements . 18
8.3 Tracking index test, IEC 60112 . 18
8.3.1 Purpose and principle . 18
8.3.2 Test method . 18
8.3.3 Relevance of test data . 19
9 Resistance to rusting . 19
9.1 General . 19
9.2 Requirements . 19
9.3 Test . 19
10 Legibility, durability and indelibility of marking . 20
10.1 General . 20
10.2 Requirements . 20

10.3 Test . 20
11 Screw-type terminals for connecting conductors . 21
12 Criteria for tests in accessory standards . 21
13 Tolerances . 21
14 Mechanical strength . 22
14.1 Impact. 22
14.2 Free fall . 22
15 Appropriate dimensioning of insulation distances . 22
15.1 General . 22
15.2 General information . 22
15.3 Dimensioning of clearances . 23
15.4 Dimensioning of creepage distances . 23
15.5 Dimensioning of solid insulation . 25
15.6 Dimensioning of functional insulation . 25
15.7 Practical application of the IEC 60664 series with regards to particular
questions . 25
15.8 Other information useful for TC 23 and its subcommittees . 25
16 Resistance to UV . 26
16.1 General . 26
16.2 Basic principles . 27
16.3 Tests . 27
16.3.1 General . 27
16.3.2 UV test . 27
16.3.3 Mechanical test . 28
Annex A (informative) Material selection process . 29
A.1 General . 29
A.2 Requirements for material selection process . 29
A.3 Material selection process. 30
A.3.1 Material selection based on flammability classifications . 30
A.3.2 Arc ignition test . 30
Annex B (informative) Suggested GWEPT temperatures . 32
Bibliography . 33

Figure 1 – Thread-forming screw . 11
Figure 2 – Thread-cutting screw . 12
Figure 3 – Small parts . 17
Figure 4 – Test piston dimensions. 21

Table 1 – Torque per thread diameter . 14
Table A.1 – Minimum glow-wire ignition temperature (GWIT) of insulating materials
required for the flammability classification of the selected material . 30
Table A.2 – Minimum glow-wire ignition temperature (GWIT) of insulating materials
required for the GWFI classification of the selected material . 30
Table A.3 – Minimum number of arcs required for the flammability classification of the
selected material . 30
Table A.4 – Minimum number of arcs required for the GWFI classification of the
selected material . 30

– 4 – IEC TR 61916:2017 © IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL ACCESSORIES –
HARMONIZATION OF GENERAL RULES

FOREWORD
...