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Résumé :
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. Data-Driven Standard Updates: Major standards bodies (ITU-T, Telcordia, IEEE, IEC) dynamically update overvoltage and overcurrent resistibility requirements when statistical A field return rate of 1-2% or higher for critical functions is typically considered sufficient to trigger formal RCA and standards review. . Sequential Root Cause Analysis (RCA) Methodology: Physical root cause analysis progresses from non-destructive techniques (visual, X-ray) to destructive testing (decapsulation, SEM/EDX) to conclusively determine failure origins. . Distinct Damage Signatures: Components such as MOVs, TVS diodes, and PCB traces exhibit unique physical and chemical damage patterns that differentiate environmental overstress (e.g., lightning) from installation faults (e.g., poor grounding). . Misattribution of Field Failures: Case studies reveal that equipment damage initially attributed to environmental power surges is frequently caused by improper installation, such as ground loops or incorrect mounting hardware. . Targeted Corrective Actions: When failures stem from user or installation errors, manufacturers favor improving installation manuals, implementing Poka-Yoke designs, and issuing field notices rather than needlessly increasing product test resistibility standards.
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