IEC TS 60695-2-21:2023

Fire hazard testing - Part 2-21: Glowing/hot-wire based test methods - Fire containment test on finished units

IEC 60695-2-21:2023, which is a Technical Specification, specifies a fire containment test method for finished units. It is intended to verify the capability of containing of a fire event generated by an effective ignition source inside a finished unit.
Unless otherwise specified by the relevant product standard, determination of the fire containment described in this document does not apply to any of the following:
- A single electrical component;
- A single electrical component when incorporated into a finished unit;
- Electrical installation products such as distribution boards, circuit protection devices, switchgear, controlgear, cable management system and electrical accessories (wiring devices).

General Information

• Status: Published
• Publication Date: 26-Jun-2023
• ICS: 13.220.40 - Ignitability and burning behaviour of materials and products
• Technical Committee: TC 89 - Fire hazard testing
• Drafting Committee: PT 60695-2-15 - TC 89/PT 60695-2-15
• Current Stage: PPUB - Publication issued
• Start Date: 13-Jul-2023
• Completion Date: 27-Jun-2023

Standards Content (Sample)

IEC TS 60695-2-21 ®
Edition 1.0 2023-06
TECHNICAL
SPECIFICATION
colour
inside
Fire hazard testing –
Part 2-21: Glowing/hot-wire based test methods – Fire containment test on
finished units
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IEC TS 60695-2-21 ®
Edition 1.0 2023-06
TECHNICAL
SPECIFICATION
colour
inside
Fire hazard testing –
Part 2-21: Glowing/hot-wire based test methods – Fire containment test on
finished units
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS  13.220.40 ISBN 978-2-8322-7122-3
– 2 – IEC TS 60695-2-21:2023  IEC 2023
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Test specimen . 9
4.1 General . 9
4.2 Verification of potential ignition sources . 9
4.3 Test conditions . 10
5 Test apparatus . 10
5.1 Nickel-Chromium wire (NiCr wire) . 10
5.2 Test circuit . 10
5.3 Connections . 10
5.4 Cheesecloth . 10
5.5 Test chamber . 10
5.6 Timing device . 11
6 Verification of the NiCr wire . 11
7 Conditioning . 11
7.1 Conditioning of the test specimen . 11
7.2 Conditioning of the cheesecloth . 11
7.3 Testing condition . 11
8 Test procedure . 11
8.1 Flow chart . 11
8.2 Identification of potential ignition sources . 13
8.3 Factors affecting test . 14
8.4 Application of NiCr wire. 14
8.5 Selection of NiCr wire application methodology . 15
8.6 Potential ignition source verification . 16
8.7 Test specimen fire containment verification . 17
9 Observations and measurements . 18
9.1 Initial observations . 18
9.2 Test observations . 18
10 Evaluation of test results . 18
11 Test report . 19
12 Information to be given in the relevant product standard . 19
Annex A (normative) Interpretations of the location of the cylindrical volume . 20
Annex B (normative) NiCr wire application methods – Internal coil winding method . 21
B.1 General . 21
B.2 Insulating material cavity preparation . 21
B.3 NiCr wire coil preparation . 21
Annex C (normative) NiCr wire application methods – External winding method . 24
C.1 General . 24
C.2 Insulated connections winding method . 24
C.3 Non-insulated connections winding method . 25
C.4 Examples of electrical connections applying the external winding method . 26

C.4.1 General . 26
C.4.2 Insulated terminals providing mechanical support function . 26
C.4.3 Insulated terminals with one side not accessible . 26
Annex D (informative) Examples of supply wires fixation methodologies . 28
D.1 General . 28
D.2 Fixation over existing electrical connection supply harness . 28
D.3 Fixation over surrounding parts . 28
Bibliography . 30

Figure 1 – Test procedure flow-chart. 12
Figure 2 – Insulating material cavity cross sectional dimensions . 16
Figure 3 – NiCr wire application methodology selection flow-chart . 16
Figure A.1 – Examples of the location of the cylindrical volume . 20
Figure B.1 – Winding tool . 22
Figure B.2 – Example 1 of NiCr wire coil application . 23
Figure B.3 – Example 2 of NiCr wire coil application . 23
Figure B.4 – Example 3 of NiCr wire coil application . 23
Figure C.1 – Single connection insulating material external winding – Side View . 24
Figure C.2 – Single connection insulating material external winding – Front view . 25
Figure C.3 – Example of non-insulated single terminal electrical connection . 26
Figure C.4 – Example of insulated terminals providing mechanical support function. 26
Figure C.5 – Example of insulated terminal with one side not accessible . 27
Figure D.1 – Fixation over existing harness by stripe . 28
Figure D.2 – Fixation over surrounding parts by adhesive tape – Side view . 29
Figure D.3 – Fixation over surrounding parts by adhesive tape – Top view . 29

Table B.1 – Drill bit and winding tool dimensions . 22

– 4 – IEC TS 60695-2-21:2023  IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIRE HAZARD TESTING –
Part 2-21: Glowing/hot-wire based test methods –
Fire containment test on finished units

FOREWORD
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