How to choose the sensitivity and range of piezoelectric acceleration sensor?
Piezoelectric accelerometers are the main sensors for vibration measurement. Although the piezoelectric accelerometer has a wide measuring range, it has been widely used in the market
accelerometer
There are many varieties, so it brings some difficulty to the correct selection. As a general principle for the selection of vibration sensors, the correct selection should be based on the analysis and estimation of the following three aspects of the measured signal.
a. The magnitude of the measured vibration
b. Frequency range of the measured vibration signal
c. Vibration test site environment
Piezoelectric accelerometers are the main sensors for vibration measurement. Although the piezoelectric accelerometer has a wide measuring range, it has been widely used in the market
accelerometer
There are many varieties, so it brings some difficulty to the correct selection. As a general principle for the selection of vibration sensors, the correct selection should be based on the analysis and estimation of the following three aspects of the measured signal.
The following will be based on the above three aspects and refer to the relevant technical indicators of the sensor to further discuss the specific selection.
Sensitivity and range of the sensor
The sensitivity of sensor is one of the basic indexes of sensor. The sensitivity of the sensor directly affects the measurement of vibration signal. It is not difficult to understand that the sensitivity of the sensor should be based on the measured vibration (acceleration value) size, but because the piezoelectric acceleration sensor is to measure the acceleration value of the vibration, and under the same displacement amplitude conditions, the acceleration value is proportional to the square of the frequency of the signal, so the size of the acceleration signal in different frequency bands is very different. For the low-frequency vibration of large structures, the acceleration value of the vibration quantity may be quite small. For example, when the vibration displacement is 1mm, the acceleration value of the signal with a frequency of 1 Hz is only 0.04m/s2 (0.004g). However, for high frequency vibration, when the displacement is 0.1mm and the frequency is 10 kHz, the acceleration value can reach 4 x 10 5m/s2 (40000g). Therefore, although the piezoelectric acceleration sensor has a large measurement range, the vibration signal used to measure the high and low frequencies should be fully estimated when selecting the sensitivity of the acceleration sensor. The commonly used vibration measurement piezoelectric accelerometer sensitivity, voltage output type (IEPE type) is 50-100 mV/g, charge output type is 10-50 pC/g.
