Influence of Overcurrent Value on Thermal Degradation Process of Flame-Retardant XLPE Copper Wire

DOI: https://doi.org/10.62517/jes.202602130

Author(s)

Shunan Zhou*, Haining Rong, Tiancheng Liang, Fengbo Yuan, Nanbo Huang

Affiliation(s)

China People's Police University, Langfang, Hebei, China *Corresponding Author

Abstract

Flame-retardant cross-linked polyethylene (XLPE) insulated copper wires are widely used in hazardous environments, yet systematic studies on their pyrolysis behavior under slight overcurrent conditions remain scarce. This study investigates the thermal degradation characteristics of flame-retardant XLPE copper wires subjected to slight overcurrent values (70-100 A) using thermogravimetric analysis at heating rates of 10-40 °C/min. Results indicate that the pyrolysis process comprises three stages with two distinct mass loss peaks. The total mass loss stabilizes at 58±2% (90% occurring at 200-520 °C), with residual mass of 42%. Characteristic temperatures shift to lower values as overcurrent increases, with 100 A samples showing a 10 °C forward shift in the third stage. The 20 °C/min heating rate approaches maximum pyrolytic state. At 100 A, outer insulation exhibits significant degradation with reduced mass loss (43±2%), suggesting this as the critical threshold for kinetic parameter variation. These findings provide theoretical support for identifying slight overcurrent faults in fire investigations.

Keywords

Flame-Retardant XLPE Copper Wire; Slight Overcurrent; Pyrolysis Characteristics; Thermogravimetric Analysis; Fire Investigation

References

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