This part of IEC 60904 describes the procedures used to measure the dependence of any electrical parameter (Y) of a photovoltaic (PV) device with respect to a test parameter (X) and to determine the degree at which this dependence is close to an ideal linear (straight-line) function. It also gives guidance on how to consider deviations from the ideal linear dependence and in general on how to deal with non-linearities of PV device electrical parameters. Typical device parameters are the short-circuit current I SC , the open-circuit voltage V OC and the maximum power P max . Typical test parameters are the temperature T and the irradiance G. However, the same principles described in this document can be applied to any other test parameter with proper adjustment of the procedure used to vary the parameter itself.
