BS EN IEC 60332-3-25:2018

What is IEC 60332‑3‑25 -Best guidelines for testing electric cables and optical fibres about?

IEC 60332‑3‑25 covers category D for methods of test for the assessment of vertical flame spread of vertically mounted bunched wires or cables, electrical or optical, under defined conditions

IEC 60332‑3‑25 relates only to small cables of overall diameter 12 mm or smaller and cross-section of 35 mm2 or smaller installed on the test ladder to achieve a nominal total volume of non-metallic material of 0,5 l/m of the test sample. The flame application time is 20 min. The method of mounting uses the front of the standard ladder in touching formation only. The category is intended for use with small cables where very low volumes of non-metallic material are required to be evaluated.

Note: For IEC 60332‑3‑25 the term "electric wire or cable" covers all insulated metallic conductor cables used for the conveyance of energy or signals.

Who is IEC 60332‑3‑25 -Best guidelines for testing electric cables and optical fibres for?

IEC 60332‑3‑25 on testing of electric and optical fibre is useful for:

• Technicians and electricians
• Manufacturing unit of electric cables
• Quality assurance team
• The professional workers who are involved in the installation of electric wiring manually

Why should you use IEC 60332‑3‑25-Best guidelines for testing electric cables and optical fibres?

IEC 60332‑3‑25 defines the various categories and the relevant procedures. The categories are distinguished by test duration, the volume of non-metallic material of the test sample and the method of mounting the sample for the test. In all categories, cables having at least one conductor of cross-sectional area greater than 35 mm2 are tested in a spaced configuration, whereas cables of conductor cross-sectional area of 35 mm2 or smaller and optical fibre cables are tested in a touching configuration.

IEC 60332‑3‑25 series specify methods of test for flame spread characteristics for a single vertical insulated wire or cable.

IEC 60332‑3‑25 also covers the cable features as mentioned below:

• The volume of combustible material exposed to the fire and to any flame which may be produced by the combustion of the cables
• The geometrical configuration of the cables and their relationship to an enclosure
• The temperature at which it is possible to ignite the gases emitted from the cables
• The quantity of combustible gas released from the cables for a given temperature rise
• The volume of air passing through the cable installation
• The construction of the cable, for example, armoured or unarmoured, multi-, or single core.

What’s changed since the last update?

BS EN IEC 60332‑3‑25:2018 supersedes BS EN 60332‑3‑25:2009 BS EN IEC 60332‑3‑25:2018 includes some technical changes concerning BS EN 60332‑3‑25:2009. These include:

• Adjustments have been made to the title, and elsewhere, to emphasise the standard applies to optical fibre cables as well as metallic conductor types
• Details of how cables are mounted on the ladder have been better defined to improve repeatability and reproducibility.