Concepts for detecting a deterioration state of a load bearing capacity in a suspension member arrangement for an elevator

摘要

Methods and devices detect a deterioration state of a load bearing capacity in an elevator suspension member arrangement having several suspension members, such as belts, including electrically conductive cords incorporated into an elastomer material. Deterioration is determined by applying alternating electric voltages to the cords included in legs of a circuitry. Phase shifts between the alternating voltages, for example by determining sum voltages and/or differential voltages, provide valuable information about a condition of the belt. A fixation arrangement of the suspension member arrangement is adapted to enable or simplify the proposed measurements. Furthermore, counting a number of performed bending cycles provides further information to be taken into account for determining the current deterioration state of the belts. Overall, deteriorations in a suspension member such as broken cords, shunts between cords, connections between cords and ground potential and/or deterioration due to corrosion of cords may be easily detected.