Low Smoke Halogen-Free Cable (LSZH Cable), featuring low smoke, halogen-free (compliant with IEC 60754 standards), flame retardant, and environmental-friendly properties, is widely used in construction engineering, rail transit, data centers, power systems, and public facilities. Its long-term reliability depends not only on installation and environmental conditions but also on the performance of LSZH insulation compounds and sheathing compounds.
I. Common Failure Types
Major failures of LSZH cables include mechanical damage, insulation moisture ingress, aging, overvoltage, cable overheating, and accessory failure. The main inducing factors are as follows:
Prolonged Overload Operation: Conductor heating exposes insulation layer and LSZH sheath to high temperatures for extended periods, prone to thermal-oxidative aging, reducing electrical and mechanical properties. Meanwhile, the copper conductor may accelerate insulation material oxidation (copper-catalyzed degradation).
Installation Issues: Poor joint sealing or sheath damage allows moisture ingress into insulation layer; insufficient bending radius may cause stress concentration, increasing cracking risk.
Environmental and External Force Impacts: Prolonged water immersion, external extrusion, or municipal construction damage can harm sheath and insulation structure.
Chemical Corrosion: In acidic/alkaline or salt spray environments, sheath and armor may corrode, affecting overall structural stability.
Material and Accessory Quality Issues: Unstable performance of insulation compounds, sheathing compounds, or cable accessories may cause partial discharge, cracks, or overvoltage, severely affecting system safety.
II. Main Causes of Aging
LSZH cable aging results from the combined effects of electrical, thermal, mechanical, and environmental factors:
Thermal Aging and Copper-Catalyzed Degradation: Long-term high temperature causes molecular chain scission or oxidation in LSZH materials. Cross-linked LSZH offers better heat resistance, with uniformity affecting long-term performance; thermoplastic LSZH excels in flexibility and processability.
Moisture Ingress and Water Treeing Effect: For medium and high voltage cables, insulation moisture ingress readily forms water tree structures, gradually weakening insulation strength; low voltage cables mainly exhibit insulation resistance reduction.
Chemical Corrosion and Mechanical Stress: Acidic/alkaline or electrolytic corrosion, poor joint workmanship, and insufficient bending radius cause stress concentration, leading to premature cracking of insulation and sheath.
III. Importance of High-Performance LSZH Cable Materials
Stable LSZH materials are key to ensuring long-term reliable operation of cables:
Insulation Compounds: Excellent electrical properties, resistance to copper-catalyzed degradation, stable thermal aging resistance
Sheathing Compounds: Good flame retardancy and low smoke characteristics, high mechanical strength, cracking resistance, and strong resistance to moisture and heat
ONE WORLD specializes in cable material solutions, providing high-quality LSZH insulation compounds, LSZH sheathing compounds, and various cable construction materials, widely used in power cables, communication cables, and specialty cables, helping customers enhance safety and long-term reliability.
Post time: Feb-28-2026