9 ELECTRICAL AND ELECTRONIC INDUSTRIAL CONTROL SYSTEMS INCORPORATING RELAYS, MICRO-PROCESSORS, DRIVES, AND MOTORS TO CONTROL MACHINE TOOLS AND MACHINERY; INDUSTRIAL ELECTRONIC SENSORS TO SENSE THE PRESENCE OF FERROUS AND NON-FERROUS METALS; THICKNESS MEASURING UNITS TO MEASURE THE THICKNESS OF ANY KIND OF STRIP MATERIAL, SUCH AS METAL OR PLASTIC, THAT IS EITHER STATIONARY OR IN MOTION