A device for detecting wear, the device comprising: an electrically resistive material having a face (31, 33) for engaging a mechanical contact member (81, 82, 83) and an outer surface separate from the face; at least two primary electrodes (232, 233, 234, 235) spaced apart from each other and overlying or embedded within the outer surface of the electrically resistive material a secondary electrode on an opposite surface to the outer surface of the electrically resistive material; a plurality of resistive zones (236, 237, 238, 239) separated from each other, each of the resistive zones (236, 237, 238, 239) extending in the electrically resistive material between ones of the primary electrodes (232, 233, 234, 235) and the secondary electrode; a resistive network coupled to the primary electrodes (232, 233, 234, 235) at respective measurement nodes to form resistive voltage dividers (71, 72, 73, 74); an analog multiplexer coupled to the primary electrodes (232, 233, 234, 235) via the resistive network and adapted to select respective ones of the primary electrodes (232, 233, 234, 235) or their respective measurement nodes; a data storage device for storing reference data comprising reference measurement voltage versus a wear level of the electrically resistive material for each corresponding resistive zone (236, 237, 238, 239); and an electronic data processor adapted to determine the wear level or degree of removal of the resistive material from the face of the electrically resistive material based on any observed change in voltage at the measurement nodes with respect to each initial voltage or each reference voltage for the corresponding resistive zone (236, 237, 238, 239) at the respective measurement node, where the change in voltage is indicative of the wear level or the degree of removal of resistive material from a face of the electrically resistive material, where the change in voltage is continuously variable and not limited to discrete wear levels. an electrically resistive material having a face (31, 33) for engaging a mechanical contact member (81, 82, 83) and an outer surface separate from the face; at least two primary electrodes (232, 233, 234, 235) spaced apart from each other and overlying or embedded within the outer surface of the electrically resistive material a secondary electrode on an opposite surface to the outer surface of the electrically resistive material; a plurality of resistive zones (236, 237, 238, 239) separated from each other, each of the resistive zones (236, 237, 238, 239) extending in the electrically resistive material between ones of the primary electrodes (232, 233, 234, 235) and the secondary electrode; a resistive network coupled to the primary electrodes (232, 233, 234, 235) at respective measurement nodes to form resistive voltage dividers (71, 72, 73, 74); an analog multiplexer coupled to the primary electrodes (232, 233, 234, 235) via the resistive network and adapted to select respective ones of the primary electrodes (232, 233, 234, 235) or their respective measurement nodes; a data storage device for storing reference data comprising reference measurement voltage versus a wear level of the electrically resistive material for each corresponding resistive zone (236, 237, 238, 239); and an electronic data processor adapted to determine the wear level or degree of removal of the resistive material from the face of the electrically resistive material based on any observed change in voltage at the measurement nodes with respect to each initial voltage or each reference voltage for the corresponding resistive zone (236, 237, 238, 239) at the respective measurement node, where the change in voltage is indicative of the wear level or the degree of removal of resistive material from a face of the electrically resistive material, where the change in voltage is continuously variable and not limited to discrete wear levels.