With a multiterminal technique we have studied the behavior of the in-plane voltage in high-T c superconducting YBa 2 Cu 3 O 7 films as a function of temperature T, magnetic field B and distance from the input current electrodes. Regions with different superconducting transition temperatures were obtained by selective sputtering between gold electrodes. The non-local voltages, measured outside of the direct current path, show an excess signal near the critical temperature T c (B) which resembles that measured in different superconductors and attributed partially to charge imbalance effects, the presence of phase-slip centers and vortex-antivortex-interactions. We have determined the decay length of the non-local voltages as a function of field and temperature. We compared and analyzed the excess voltage and decay length with a current distribution model and an equivalent circuit of resistances. This model accounts for all the measured behavior of the non-local voltages and of the decay length. We discuss also estimates of the decay length based on charge imbalance and vortex correlations models.