Requirements for cables as categories of construction products and thermal resistance of power cables

Abstract

Introduction. One of the main driving factors of the demand for cable and conductor products is the modern trend of urbanization, which leads to an increase in cities with significantly increased requirements for electrical networks of transportation and distribution of electrical energy. This requires the development of appropriate infrastructure with significant demand for electricity in the commercial, industrial and residential sectors. The construction industry uses a wide range of cables with an appropriate set of electrical and mechanical properties, resistance to the influence of external climatic factors, and, first of all, must meet fire safety requirements. Increasing construction activity is stimulating the market for fire-resistant cables in the construction industry. According to the Construction Products Regulation, power, telecommunication cables, data cables, control and management, fiber optic refer to construction products in the EU member states. These cables are intended for the supply of electrical energy and communication, which are permanently installed in buildings and other engineering structures. Power, telecommunications, data and control cables are considered construction products, and are the only electrical products classified as construction. Over the next 15 years, Eastern Europe is expected to see increased growth in the construction industry, as the end of the war in Ukraine requires nearly $1 trillion in reconstruction. A strategic task in the reconstruction of the country is the use of cable and conductor products with increased operational properties, including in the construction industry. Significant efforts and investments in innovation and certification of cable and conductor products require manufacturers to create construction products of the «Power, control and communication cables» category with a high level of fire safety in accordance with the Euroclassification of cables in terms of reaction to fire depending on the level of safety. Purpose. Analysis of fire safety requirements for cables as a category of construction products and determination of thermal resistance of power cables based on experimental thermal studies of modern electrical insulating compositions. Methodology. The thermal stability of power cables with a voltage of 0,66/1 kV was determined, depending on the design, based on the conducted experimental studies of the thermal stability of electrical insulation materials, between the core filling and the polymer sheath, removed from the cable samples. On the basis of the conducted correlation analysis between thermal resistance and fire load, which are important parameters for confirming the quality and safety of the entire cable, it has been proven that the efficiency of halogen-free compositions to meet fire safety requirements increases with the increase in the cross-section and number of cores in the cable. Practical value. Determining the heat load and fire resistance of cables of various designs and areas of application based on the obtained experimental data on the heat of combustion of polymer cable materials is necessary and justified at the stage of mastering and determining the prospects for the production of cables with modern halogen-free electrical insulation compositions in accordance with fire safety requirements.