After publishing the NVH diagnosis case of abnormal noise of the gearbox at the start of the GL8 ES in 18 years , careful users asked the following questions: The measurable frequency range on the TA143 accelerometer specification table is 0-350Hz, which is for vibrations exceeding 350Hz Is the data measurement accurate? Is the specification parameter wrong?
Next, I will briefly answer the above questions for you.
When capturing vibration data, we can use acceleration sensors to collect frequency signals up to 2000 Hz. In the frequency chart, the acceleration sensor can help us find the frequency points that are really problematic. As the user mentioned, the frequency range on the specification table is 0-350Hz. This is because the frequency range of human perception of vibration is 0-200Hz. When the signal frequency exceeds 350Hz, it is best to use the acceleration sensor as a microphone.
The following post describes how to use the accelerometer as a microphone to listen to vibration: Use the accelerometer as a microphone to listen to vibration
We use an acceleration sensor to collect a segment of signals. Suppose we suspect that the fault frequency is 1000 Hz based on the acceleration sensor data. At this time, it is best to add a microphone, and then check whether there is an annoying spike in 1000Hz in the data captured by the microphone, so that you can verify again whether 1000Hz is the "problem" frequency point.
In fact, the TA143 acceleration sensor can collect frequency signals up to 1600 Hz on the X axis and Y axis, and the highest frequency on the Z axis is 500 Hz. The natural frequency of the acceleration sensor is about 5500 Hz.
However, many times of NVH diagnosis experience tells us that the accelerometer still has high accuracy for measuring vibration data above 350Hz . Even with high frequency vibrations above 350 Hz, the vibration frequency that is annoying can be accurately found.