Using previous works on the second geometrization, we can now submit a method to use xTAN formalisme in order to study theoretically networks (xTAN means extended tensorial analysis of networks). A first application consists in the identication of risk in electromagnetic compatibility. But on this example, many others can be developed in various jobs including multiphysic ones. We detail the methodology through each of its steps: network graphs, equations, jacobian matrix and Kron's metric, linked parametrized surface, metric and sources, susceptibility spectrum, excitation spectrum and nally analysis.