When an electrical machine suffered a mechanical fault, it generally emits certain sounds. These sounds came from the vibration. Therefore, based on the vibration, it could be detected if there was a mechanical fault in an electrical machine. This paper discussed the graphical display of the vibration of electrical machines in the form of household water pumps which were in good condition, faulty bearing, faulty impeller, or faulty foot valve. Vibration could be displayed in the time domain, or in the frequency domain, by using the three axes, i.e. X, Y, and Z. In the frequency domain, the vibration could be displayed at various frequency resolutions. Based on the observations, the higher frequency resolution, the lower detail in the graphical display of frequency domain would be shown. Although there was lower detail in the graphical display of frequency domain, at frequency resolution of 11.7 Hz in the X axis, showed that it could be visually distinguished among water pumps which were in good condition, faulty bearing, faulty impeller, or faulty foot valve.

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When an electrical machine suffered a mechanical fault, it generally emits certain sounds. These sounds came from the vibration. Therefore, based on the vibration, it could be detected if there was a mechanical fault in an electrical machine. This paper discussed the graphical display of the vibration of electrical machines in the form of household water pumps which were in good condition, faulty bearing, faulty impeller, or faulty foot valve. Vibration could be displayed in the time domain, or in the frequency domain, by using the three axes, i.e. X, Y, and Z. In the frequency domain, the vibration could be displayed at various frequency resolutions. Based on the observations, the higher frequency resolution, the lower detail in the graphical display of frequency domain would be shown. Although there was lower detail in the graphical display of frequency domain, at frequency resolution of 11.7 Hz in the X axis, showed that it could be visually distinguished among water pumps which were in good condition, faulty bearing, faulty impeller, or faulty foot valve.

Abstract-One way in recognizing mechanical faults of electrical machines is using the vibration signals. This paper studies the recognition of mechanical faults of electrical machines which have faulty bearing, faulty impeller, and faulty foot valve. Electrical machines studied in this paper are household water pumps. The recognition of mechanical faults is conducted using the vibration signals at the frequency domain at various frequency resolution. The recognition method used is template matching for pattern classes. Euclidean distance function is used in this template matching. Based on the results, the highest recognition rate of 100% is optimally obtained using the vibration signal at frequency resolution of 5,9 Hz, and the number of 5 samples/classes in the water pump database. The 5,9 Hz frequency resolution was obtained using a 256 point FFT, where the number of 128 FFT coefficients are used as the feature extraction.Intisari-Salah satu cara pengenalan kerusakan mekanis mesin listrik adalah dengan menggunakan sinyal getaran. Tulisan ini membahas pengenalan kerusakan mekanis mesin listrik yang mempunyai kerusakan bantalan, impeller, atau pun katup kaki. Mesin listrik yang dibahas dalam tulisan ini adalah pompa air skala rumah tangga. Pengenalan kerusakan mekanis dilakukan menggunakan sinyal getaran pada ranah frekuensi, pada berbagai resolusi frekuensi. Metode pengenalan yang digunakan adalah pencocokan template pada kelas-kelas pola. Fungsi jarak Euclidean digunakan dalam pencocokan template ini. Berdasarkan hasil pengujian, tingkat pengenalan tertinggi 100% secara optimal diperoleh menggunakan sinyal getaran pada resolusi frekuensi 5,9 Hz, dan sejumlah 5 sampel/kelas pada basis data pompa air. Resolusi frekuensi 5,9 Hz ini diperoleh menggunakan FFT 256 titik dengan sejumlah 128 koefisien FFT yang digunakan sebagai ekstraksi cirinya.Kata Kunci-pompa air, kerusakan mekanis, sinyal getaran, ranah frekuensi, resolusi frekuensi.