Dynamic rating of supply cables of a stabilizing furnace

Supply cables of electric stabilizing furnaces represent considerable investments. Presently the cross-section of cables is selected in reference to maximum safety, but usually the cable is over-dimensioned and especially in the case of dynamic loading. In this paper we propose a way of calculating dynamic cable rating which utilizes Finite Element Analysis (FEA) and Thermal Network Method (TNM). Resistive losses of the cable, involving proximity and skin effects, are calculated using FEA as an input to a thermal model based on TNM. The model is compared with parameters provided by manufacturers and applied on a real load curve of the furnace.