During determining of equivalent circuit elements, based on experimental impedance spectra, various cases can occur. It should be noted that most often only modulus and the angle of their impedance are measured for ceramic materials. On the basis of these measurements, it is very demanding to distinguish values of certain elements of equivalent circuit. Which of RC elements, of the basic equivalent circuit from Fig. 1, will be detected depends on the characteristic being considered, as well as on relative relation of the equivalent
circuit elements values, as analysed already in Figs. 2-5. While impedance characteristic is more appropriate for determining RC element with higher resistance, electric modulus is more appropriate for determining RC element with lower capacitance.