This work presents a method to obtain the one‐exponential model parameters of a series–parallel association of photovoltaic (PV) devices. From the linear expressions of the I–V characteristic in short‐circuit and open‐circuit zones, simple equations for association model parameters are obtained based on cell parameters. In order to validate the model, measurements have been performed in the 33 cells of a conventional PV module previously modified to have access to its cells, either individually or associated. Series and parallel proposed models have been applied to measurements, supposing all module cells are connected either in series or in parallel. Good approximations have been found in both cases. The method here proposed supplies a useful formulation that can be used in simulation programmes and array calculations. Copyright © 2005 John Wiley & Sons, Ltd.