Improvement of test methods and criteria for evaluation of resistance to flame propagation of long elements of the wiring system

Authors

DOI:

https://doi.org/10.15587/1729-4061.2021.249105

Keywords:

electrical product, electrical and optical cable, conduit, fire safety, flame propagation, wiring system

Abstract

The test methods for flame propagation of long elements of the electrical wiring system, in particular, cables, cable conduits and ducts, are analyzed, and differences in them are found in the test conditions and criteria for evaluating the resistance to flame propagation.

Using a substrate of a wooden board covered with a layer of tissue paper with an areal density of (21±9) g/m2, adopted for testing other elements of the electrical wiring system, a cable was identified that is not resistant to flame propagation. It is proposed to use this substrate for testing the flame propagation of cables instead of a substrate made of a double layer of filter paper with a surface density of (80±15) g/m2.

In one of three experiments, a cable that was not resistant to flame propagation was found based on the criterion of the presence of ignition of the substrate located under it. To reduce the risk of making an incorrect decision on compliance, it is proposed that the assessment of long elements of the wiring system be carried out according to the rules established for cable ducts, trays and ladders in EN 50085-1 and IEC 61537.

For the AVVG cable with an outer diameter of 10 mm to 60 mm, when it touches the blue flame cone of 1 kW, the correlation coefficient of the dependence of the length of the charred part on the diameter was 0.969. For a distance of 100 mm between the sample and the burner along its axis, a correlation coefficient of 0.985 was obtained. It is proposed to test cables under the second condition recommended in IEC 60695-11-2.

For two conduits, flame propagation was revealed when exposed to a 1 kW flame for 120 s and 240 s. However, for these pipelines, flame propagation did not occur under standard conditions of exposure to such a flame for 20 s and 25 s. To identify long elements of the wiring system that are not resistant to flame propagation, it is proposed to test them at a duration of exposure to a flame of 1 kW, established for cables in IEC 60332-1-2

Author Biographies

Rostyslav Kravchenko, Institute of Public Administration and Research in Civil Protection

Head of Department

Department of Technical Regulation

Center of Research in Fire Protection

Pavlo Illiuchenko, Institute of Public Administration and Research in Civil Protection

Head of Department

Department of Electrical Products

Research and Testing Center

Andrii Onyshchuk, Institute of Public Administration and Research in Civil Protection

Junior Researcher

Department of Electrical Products

Research and Testing Center

Oleksandr Zazymko, Institute of Public Administration and Research in Civil Protection

Researcher

Department of Electrical Products

Research and Testing Center

References

  1. IEC 60695-1-10:2016 Fire hazard testing – Part 1-10: Guidance for assessing the fire hazard of electrotechnical products – General guidelines (2016). Geneva: International Electrotechnical Commission, 50.
  2. IEC 60695-1-30:2017 Fire hazard testing Part 1-30: Guidance for assessing the fire hazard of electrotechnical products – Preselection testing process – General guidelines (2017). Geneva, International Electrotechnical Commission, 31. doi: http://doi.org/10.3403/02683772u
  3. Huang, X., Zhu, H., He, L., Peng, L., Cheng, C., Chow, W. (2021). Improved model for estimating sidewall effect on the fire heat release rate of horizontal cable tray. Process Safety and Environmental Protection, 149, 831–838. doi: http://doi.org/10.1016/j.psep.2021.03.040
  4. Li, L., Huang, X., Bi, K., Liu, X. (2016). An enhanced fire hazard assessment model and validation experiments for vertical cable trays. Nuclear Engineering and Design, 301, 32–38. doi: http://doi.org/10.1016/j.nucengdes.2015.12.034
  5. An, W., Wang, T., Liang, K., Tang, Y., Wang, Z. (2020). Effects of interlayer distance and cable spacing on flame characteristics and fire hazard of multilayer cables in utility tunnel. Case Studies in Thermal Engineering, 22. doi: http://doi.org/10.1016/j.csite.2020.100784
  6. An, W., Wang, X., Tang, Y., Wang, T., Lu, J. (2021). Influence of cable inclination angle and longitudinal ventilation on temperature distribution during cable fire in utility tunnel. Case Studies in Thermal Engineering, 27. doi: http://doi.org/10.1016/j.csite.2021.101304
  7. Sundström, B., Axelsson, J., Van Hees, P. (2003). A proposal for fire testing and classification of cables for use in Europe. SP Swedish National Testing and Research Institute, 38.
  8. EN 13501-6:2018 Fire classification of construction products and building elements – Part 6: Classification using data from reaction to fire tests on power, control and communication cables (2018). Brussels: European Committee for Standardization, 30. doi: http://doi.org/10.3403/30348257
  9. Regulation (EU) No. 305/2011 of the European Parliament and of the Council of 9 March 2011 laying down harmonized conditions for the marketing of construction products and repealing Council Directive 89/106/EEC (2011). OJ L 88, 4.4.2011, 5–43.
  10. Johansson, R., Post, J., Försth, M. (2015). Extended field of application (EXAP) for reaction-to-fire Euro-classification of optical fibre cables. SP Technical Research Institute of Sweden. SP Report, 49.
  11. Kaczorek-Chrobak, K., Fangrat, J. (2019). Influence of Constructional-Material Parameters on the Fire Properties of Electric Cables. Energies, 12 (23), 4569. doi: http://doi.org/10.3390/en12234569
  12. Directive 2014/35/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of electrical equipment designed for use within certain voltage limits. OJ L 96, 29.3.2014. Р. 357–374.
  13. IEC 60332-1-2:2004 Tests on electric and optical fibre cables under fire conditions – Part 1-2: Test for vertical flame propagation for a single insulated wire or cable – Procedure for 1 kW pre-mixed flame (2004). Geneva: International Electrotechnical Commission, 21. doi: http://doi.org/10.3403/03171042
  14. IEC 60332-1-3:2004 Tests on electric and optical fibre cables under fire conditions – Part 1-3: Test for vertical flame propagation for a single insulated wire or cable – Procedure for determination of flaming droplets/particles (2004). Geneva: International Electrotechnical Commission, 21.
  15. IEC 60332-1-2:2004/AMD1:2015 Tests on electric and optical fibre cables under fire conditions – Part 1-2: Test for vertical flame propagation for a single insulated wire or cable – Procedure for 1 kW pre-mixed flame (2015). Geneva, International Electrotechnical Commission, 9.
  16. IEC 60332-1-3:2004/AMD1:2015 Tests on electric and optical fibre cables under fire conditions – Part 1-3: Test for vertical flame propagation for a single insulated wire or cable – Procedure for determination of flaming droplets/particles (2015). Geneva, International Electrotechnical Commission, 9. doi: http://doi.org/10.3403/03172788
  17. EN 60332-1-2:2004/A11:2016 Tests on electric and optical fibre cables under fire conditions – Part 1-2: Test for vertical flame propagation for a single insulated wire or cable – Procedure for 1 kW pre-mixed flame (2016). Brussels: European Committee for Electrotechnical Standardization, 4.
  18. EN 60332-1-2:2004/A12:2020 Tests on electric and optical fibre cables under fire conditions – Part 1-2: Test for vertical flame propagation for a single insulated wire or cable – Procedure for 1 kW pre-mixed flame (2020). Brussels: European Committee for Electrotechnical Standardization, 4. doi: http://doi.org/10.3403/03171042
  19. Fr Gyppaz, F. (2012). Flame spread behavior of electric cables: Round-robin characterization of the IEC/EN 60332-1 tests. Journal of Fire Sciences, 30 (5), 404–412. doi: http://doi.org/10.1177/0734904112441918
  20. IEC 61534-1:2011+AMD1:2014+AMD2:2020 Powertrack systems – Part 1: General requirements (2020). Geneva: International Electrotechnical Commission, 285.
  21. EN 50085-1:2005 Cable trunking systems and cable ducting systems for electrical installations – Part 1: General requirements (2005). Brussels: European Committee for Electrotechnical Standardization, 43.
  22. IEC 61537:2006 Cable management – Cable tray systems and cable ladder systems (2006). Geneva: International Electrotechnical Commission, 161.
  23. IEC 61386-1:2008+AMD1:2017 Conduit systems for cable management – Part 1: General requirements (2017). Geneva: International Electrotechnical Commission, 159.
  24. EN 50369:2005 Liquid tight sheathing systems for cable management (2005). Brussels: European Committee for Electrotechnical Standardization, 25. doi: http://doi.org/10.3403/30102733u
  25. IEC 60695-11-10:2013 Fire hazard testing – Part 11-10: Test flames – 50 W horizontal and vertical flame test methods. Brussels. doi: http://doi.org/10.3403/01860485u
  26. IEC 60695-11-20:2015 Fire hazard testing – Part 11-20: Test flames – 500 W flame test method. Brussels. doi: http://doi.org/10.3403/01859086u
  27. IEC 60695-11-2:2017 Fire hazard testing – Part 11-20: Test flames – 1 kW pre-mixed flame – Apparatus, confirmatory test arrangement and guidance (2017). Geneva: International Electrotechnical Commission, 40. doi: http://doi.org/10.3403/30338608
  28. Kravchenko, R. I., Illiuchenko, P. O., Onyshchuk, A. Ye. (2021). Udoskonalennia metodiv vyprobuvannia ta kryteriivotsinky stiikosti do poshyrennia polumia dovhykh elementiv systemy elektroprovodky. Problemy nadzvychainykh sytuatsii (PES-2021). Kharkiv: Natsionalnyi universytet tsyvilnoho zakhystu Ukrainy, 49–50.

Downloads

Published

2021-12-29

How to Cite

Kravchenko, R., Illiuchenko, P., Onyshchuk, A., & Zazymko, O. (2021). Improvement of test methods and criteria for evaluation of resistance to flame propagation of long elements of the wiring system. Eastern-European Journal of Enterprise Technologies, 6(10 (114), 57–68. https://doi.org/10.15587/1729-4061.2021.249105