One main concern in PLC applications is related to multipath signal transmission and poses certain problems in the prediction of the signal characteristics. In this paper a simple model, suitable for the calculation of the signal voltage and current profiles in cases of multipath PLC channels is proposed. The model is based on the nodal admittance method and can be applied in multiconductor grids, which are decoupled using modal transformations. The model is based on the transverse electromagnetic (TEM) assumption. Several test cases are investigated, including different topologies of a power distribution circuit with the random addition of branches of varying lengths. Phase to phase and phase to ground signal injection cases are examined. The results are checked against the corresponding obtained by the well-known Electromagnetic Transients Program (ATP-EMTP), showing very good agreement.