Study on Reliability of Field-Aged Photovoltaic Connectors

The paper presents the reliability study on field-aged photovoltaic connectors of different makes characterized by diverse climatic conditions with 2 to 10 years of operational life. A series of tests conforming to IEC 62852 conducted on field-aged connectors and control samples. The objective is to elucidate the mechanisms of aging and evaluate reliability of connectors, identify failure modes, potential hazards, changes in electrical and mechanical performance because of longstanding exposure to environmental and operational stresses. Field survey and testing reveal lack of awareness of workmanship and maintenance. Laboratory testing reveals connector less than 6 years of life shows low contact resistance and remain stable or have marginal linear increase after thermal and damp heat testing. Samples with life of 6 years or more from extreme climatic regions show high contact resistance with nonlinear pattern increasing to 300% in the thermal cycle and up to 600% in damp heat test. In SEM fretting was observed with high contact resistance with marginal polymer deterioration