The evaluation of the ampacity of electric power cables and theoverload protection are currently based on criteria to which theoperation of the circuits will have to satisfy each time like the firsttime, without self-memory of the way of life, without discounts or debtscorrespondent to the actual profile-load, and certainly different from asteady-state line. The number and the duration of the emergency overloadevents are taken statistically into account (IEC rules) or are fixed inadvance for an allowable average time per year over the life of thecable (ICEA approach). To enhance these criteria, the paper suggests amethod to define an equivalent prospective power cables ampacity, basedon the global allowable cables life-loss and considering the performancein time. Since monitoring and memorizing the actual life of power cablesare still not possible, the paper proposes a simple and quick evaluationmethod for the duty cycles characterized or approximated by load-phasesof continuous currents. Efforts at coordination between the protectivedevice behavior and actual cable performance in time could induceprogress in the development of a new protection joined to an operationcontrol that allows evaluation of actual load duties and memorizing theactual age of the circuits
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