In this example, you can perform FFT analysis of noise from operated product and make OK/NG determination with the operating noise level at the specified frequency bands in the analyzed data on the final testing of production line.

The LA-4441A Class1 integrating sound level meter with wide band of measurement frequency range at maximum of 20 kHz, CF-4700 FFT comparator are used in order to measure the sound level by LA-4441A with "FLAT" frequency weighting and input the signal as AC output into CF-4700.

The CF-4700 FFT comparator high-speed real-time FFT analysis of the sound level from 20 Hz to 12.5 kHz which is measured with sound level meter. The CF-4700 FFT comparator makes NG determination when the measurement value exceeds against the specified frequency band level in advance. The determination output can be used as control signal for PLC*. Also, the control signal such as start or stop of measurement can be input from PLC to CF-4700.

Sound insulating measures are required not to be influenced by the ambient sound.