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Unique mechanical properties of FLAMEBLOCKER N2XH

Unique mechanical properties of FLAMEBLOCKER N2XH

Unique mechanical properties of FLAMEBLOCKER N2XH
Karolina Zawisza – Technologist at Grupa TFKable 

N2XH halogen-free power cable, one of the FLAMEBLOCKER range of specialized fire performance installation cables; offering reduced flame propagation and low emission of corrosive fumes in the event of a fire. These cables meet the highest Construction Products Regulation (CPR) specified flammability classification B2ca–s1a,d0,a1. 
For FLAMEBLOCKER N2XH cable to attain this high CPR classification, it must also meet a series of specific fire performance testing criteria defined in dedicated European standards.  Flame propagation, smoke emission, burning droplets and the rate of heat release are determined by tests specified in the PN-EN 50399:2016 and EN 60332-1-2 standards, the corrosive gas emission is verified according to EN 60754-1,-2 standards. 

Testing performed to these European standards confirmed FLAMEBLOCKER N2XH cables achieved the highest possible classification available for this type of cable. 
The EN 50575 standard flammability classification depends on the materials used for the manufacture of a specific cable.  FLAMEBLOCKER N2XH cables have a cross-linked polyethylene (XLPE) conductor insulation and a halogen-free thermoplastic (LSOH) outer sheath material. 

Compared to conventional thermoplastic insulation, the cross-linked polyethylene has crosswise bonded long polymer chains, creating a durable three-dimensional structure that significantly improves mechanical properties at elevated temperatures, while maintaining the dielectric properties.  As a result, XLPE insulated conductors can operate at a higher maximum conductor operating temperature of +90°C and withstand a one-second short circuit temperature of +250°C.  The polyethylene cross-linking process also improves the mechanical properties, tensile strength, abrasion and impact resistance, providing more resilience and reliability during cable installation. 
FLAMEBLOCKER N2XH halogen-free outer sheath material does not include any harmful chemical elements such as fluorine, chlorine or bromine; instead the main constituents being non-organic compounds that decompose in an endothermic reaction emitting water vapour, thus inhibiting fire propagation. The halogen-free outer sheath also limits the emission of thick black smoke and the release of toxic and corrosive fumes in the event of a fire.

Thanks to the use of specialized halogen-free insulation and outer sheath materials, FLAMEBLOCKER N2XH cable is designed for installation in buildings specifying the highest fire-protection standards, especially where the safety of people and property is the critical requirement. 
FLAMEBLOCKER N2XH cable is designed for permanent installation for power and lighting systems, suitable for surface fixing in dry and humid conditions, embedded in plaster, brick or concrete walls; not recommended for direct embedding in granular pervious, vibrated or tamped concrete.