Fuel cell with protonic conduction (PEM), constitute an electrical energy source efficient and clean. The analysis of its operation requires experimental works, that allow measuring, modelling and optimizing its electrical behavior under various operating conditions. That's why it is essential to have an experimental platform that allows for easy study and control. In this work is presented the design and implementation of an open instrumental system that allows the control, measuring and determination of the operating parameters of a PEM fuel cell. As a result, shows the polarization curves, voltage-current, obtained by the system itself in different experimental conditions. These curves constitute a useful tool to assess the electrical behavior of the stack PEM.