Seismic mass acts on the piezoelectric transducer piezoelectric crystal so that the acceleration is applied to tension or compression, and a change in electrical charge on it. Typical design of the accelerometer is shown in Figure 1. Round crystal element is connected to the transmitter housing insulated bolts and washers together with the seismic mass. Electrical connections are made crystal with metal wires. Note that this design does not require a separate spring, as the bolt preload provides the sensing element.
Another way to set the piezoelectric element (Fig. 2) provides for a central rod that passes through it and is a seismic mass. In this design, the sensor itself is a "spring." The advantage of the piezoelectric accelerometer compared to other similar types of converters is that the light weight device is provided by eliminating the mounting elements for mounting the sensor. On the other hand, the system shown in Figure 1, should be strong enough and hard to eliminate the effect of the housing unit to the sensor through a loaded bolt.
High output impedance piezoelectric crystal elements makes them very sensitive to the characteristics of the connecting wires. For this reason, piezoelectric accelerometers are performed with integrated amplifier, which act as transducers of resistance.