All internally-amplified accelerometers need a power supply be it a constant current IEPE supply, a 4-20 mA loop, a 10 V bridge excitation or a bipolar +/- 15 V supply for a three-wire accelerometer. The output of the accelerometer is now conditioned to an AC voltage, whose amplitude is proportional to the amplitude of vibration with a frequency the same as the frequency of the vibration. An AC voltage signal needs further signal conditioning to retrieve any useful data.

This signal conditioning takes three main forms:

1. Overall voltage levels in either RMS or peak to peak

2. Spectral content analysis

3. Snap shot time domain analysis