A computerized method is provided for automatically determining at least one characteristic of a workpiece for processing by a plasma arc processing system. The method includes electrically connecting the workpiece to the plasma arc processing system that includes a plasma arc torch. A distal tip of the plasma arc torch is configurable to be positioned proximate to the workpiece. The method includes supplying, by the plasma arc processing system, an electrical current with a low amperage to the workpiece, the low amperage current insufficient to cut the workpiece, and monitoring, by the plasma arc processing system, a path of the electrical current relative to the workpiece. The method further includes determining, by the plasma arc processing system, the at least one characteristic of the workpiece based on the electrical current path monitored.