A new model of piezoelectric transducer is described, which makes it possible to measure a electrical signal proportional to either the shock wave voltage propagating through the rod or the deformation of the end of the rod. For the case of one-dimensional axisymmetric loading for particle displacement, a consistent derivation of the wave equation with a source in which electrical energy arises is given. The solution of the problem of describing the motion of an electro-elastic medium is based on the postulate of the continuity of elastic mechanical and electrodynamic properties of the medium. It is shown that the source on the right side of the resulting wave equation is an expression proportional to electric current or electric voltage of the piezoelectric sensor. The operation of a piezoelectric sensor mounted on the free end of the rod is considered when the duration of the shock wave pulse is longer than the time of passage of the elastic wave through the sensor material. In this case, the electrical signal taken from the piezo sensor is proportional to the acceleration of the end of the rod, and the integral of this signal is proportional to the deformation of the rod. It is also shown that the electrical voltage removed from the piezoelectric transducer placed in the middle of the rod is proportional to the mechanical stress. The operation of the piezoelectric sensor under short pulse loads, the duration of which is shorter than the time of wave passage through the thickness of the piezoelectric sensor material, is analyzed.