Fig. 4: Fan vibration measurement with designed accelerometer and B&K4381.
From: An aerosol deposition based MEMS piezoelectric accelerometer for low noise measurement
a Measured vibration signal of the fan by designed 1-axis accelerometer and B&K 4381 in frequency domain from 10 to 200 Hz. Inserted image shows the fan being measured and the two sensors placed on the fan. b–f Enlarged view of a from 10 to 40 Hz, 40 to 70 Hz, 70 to 90 Hz, 90 to 115 Hz and 115 to 200 Hz
