<abstract xmlns="http://www.w3.org/1999/xhtml">This scientific study deals with investigation of the heat of combustion and effective heat of combustion of selected electrical cables. Two different electrical cables for rated voltage of 0.6/1 kV were investigated. Both cables were power three-core with cross-section area of each core of 1.5 mm2. The cores of both cables were made of a bar cooper wire. Insulations of conductors of both cables were made of silane cross-linked polyethylene without any inorganic filler, while the bedding and outer sheath were made of polyethylene-based copolymer (the beddings were filled with two fillers - aluminium hydroxide and calcium carbonate, while the outer sheath were filled only with aluminium hydroxide). Reaction to fire class of both cables was B2ca, s1, d0, a1. The main difference in the investigated cables was that the core of one of them was wrapped in a glass mica tape (this cable showed circuit integrity maintenance under fire conditions during 180 minutes). The heat of combustion and effective heat of combustion were determined by the oxygen bomb calorimeter according to the ISO 1716:2018 standard. The highest effective heat of combustion showed the insulation of wires (for both cables 42.47 ± 0.03 MJ/kg), lower value showed outer sheath (interval form13.61 to 15.26 MJ/kg) and the lowest value was determined for bedding (interval from 4.69 to 6.39 MJ/kg). The effective heath of combustion per unit of length of both investigated cables lies in the interval from 1.37 to 1.38 MJ/m. Therefore, there is no significant difference in effective heats of combustion of the electrical cables investigated.</abstract>

This scientific study deals with investigation of the heat of combustion and effective heat of combustion of selected electrical cables. Two different electrical cables for rated voltage of 0.6/1 kV were investigated. Both cables were power three-core with cross-section area of each core of 1.5 mm2. The cores of both cables were made of a bar cooper wire. Insulations of conductors of both cables were made of silane cross-linked polyethylene without any inorganic filler, while the bedding and outer sheath were made of polyethylene-based copolymer (the beddings were filled with two fillers - aluminium hydroxide and calcium carbonate, while the outer sheath were filled only with aluminium hydroxide). Reaction to fire class of both cables was B2ca, s1, d0, a1. The main difference in the investigated cables was that the core of one of them was wrapped in a glass mica tape (this cable showed circuit integrity maintenance under fire conditions during 180 minutes). The heat of combustion and effective heat of combustion were determined by the oxygen bomb calorimeter according to the ISO 1716:2018 standard. The highest effective heat of combustion showed the insulation of wires (for both cables 42.47 ± 0.03 MJ/kg), lower value showed outer sheath (interval form13.61 to 15.26 MJ/kg) and the lowest value was determined for bedding (interval from 4.69 to 6.39 MJ/kg). The effective heath of combustion per unit of length of both investigated cables lies in the interval from 1.37 to 1.38 MJ/m. Therefore, there is no significant difference in effective heats of combustion of the electrical cables investigated.

Heat of Combustion as the Key Fire Characteristics of Electrical Cables

Slovak University of Technology in Bratislava

Faculty of Materials Science and Technology in Trnava, Institute of Integrated Safety

Research Papers Faculty of Materials Science and Technology Slovak University of Technology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

{"article-title":"Heat of Combustion as the Key Fire Characteristics of Electrical Cables"}

This scientific study deals with investigation of the heat of combustion and effective heat of combustion of selected electrical cables. Two different...

Heat of Combustion as the Key Fire Characteristics of Electrical Cables

Published Online: Sep 03, 2019

Page range: 29 - 39

Received: Apr 24, 2019

Accepted: Jun 18, 2019

DOI: https://doi.org/10.2478/rput-2019-0003

Keywords
Electrical cable, effective heat of combustion, fire load, fire risk, oxygen bomb calorimeter

© 2019 Jozef Martinka et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Heat of Combustion as the Key Fire Characteristics of Electrical Cables

Published Online: Sep 03, 2019

Page range: 29 - 39

Received: Apr 24, 2019

Accepted: Jun 18, 2019

DOI: https://doi.org/10.2478/rput-2019-0003

KeywordsElectrical cable, effective heat of combustion, fire load, fire risk, oxygen bomb calorimeter

© 2019 Jozef Martinka et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
Electrical cable, effective heat of combustion, fire load, fire risk, oxygen bomb calorimeter