The wire EDM process can be evaluated according to various criteria. In addition to the generated component quality, the cutting rate is a key performance index for the main cut. Process stability is another evaluation factor. It is defined by a resulting constant feed rate during machining and a low probability of occurrence of wire breakages. In several studies, the discharge distribution has been analyzed to predict a wire breakage. Due to the high discharge frequency, the analysis of the electrical signals has been conducted only for very short time periods. A quantitative evaluation of the continuous wire EDM process could therefore not be carried out. By implementing a real time process monitoring system, the detection of single discharges and the allocation to normal and abnormal discharges can be conducted. By using a FPGA (Field Programmable Gate Array), the characteristic discharge parameters can be analyzed in real time. The monitoring system stores only characteristic numbers and thus a continuous process can be recorded without generating a large data volume.
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