DANSK DSF/FPREN IEC 62892 PDF

This standard defines a test sequence that will quickly uncover PV module failures that have been associated with field exposure to thermal cycling for many years. This standard was specifically developed to relate to thermal fatigue failure of tabbing ribbon solder bonds, however will also apply, to some extent, to all thermal fatigue related failure mechanisms for the assemblies submitted to test. IEC 61215, the PV module qualification test, already includes an accelerated thermal cycle sequence in one leg of the testing, however, the parameters of that test only represent a qualification level of exposure. This test procedure applies more stress and will provide a route for testing to differentiate PV modules with improved durability to thermal cycling and the associated mechanical stresses. The test procedure in this standard was developed based on analysis of the stress on tin-lead solder bonds on crystalline silicon solar cells in a glass superstrate type package. Changes to the solder have an effect on the acceleration factors but not enough to change the overall results of this test. Monolithic type modules with integral cell interconnection do not suffer from this specific type of stress but there are still electrical connections within the module, for example between the integrated cell circuit and the module bus bars, that may be subject to wear out from thermal cycling. Flexible modules (without glass) are not stressed in the same way as those with glass superstrates or substrates, therefore use of the equivalency factor employed in this standard may not be applicable to these modules.