IEC TS 63140:2021 provides test methods for quantifying the permanent change in a monolithically integrated PV module’s power output that may result from some potential partial shade conditions. Three tests are available, representing conditions of use, misuse, and most severe misuse. This document is applicable to monolithically integrated PV modules with one series- connected cell group or with multiple series-connected cell groups that are in turn connected in parallel. This document is not applicable to PV modules formed by the interconnection of separate cells.
With regard to shading, PV module documentation varies significantly by manufacturer. The physical tests prescribed in this document are applied without regard to manufacturer documentation or warranty policy, which may forbid certain shadows. The tests may therefore go beyond intended use, testing a module’s response to misuse. The tests are accelerated tests. They are intended to excite similar levels of stress as shadows that are possible during an extended period of outdoor service. The tests represent adverse shadow scenarios, but not necessarily the worst case scenario, which varies by product. The procedures are performed repeatedly and in high-irradiance conditions; shadows occurring only one time or in low- irradiance conditions are likely to cause less damage. This test procedure does not comprehensively evaluate the efficacy or completeness of manufacturer recommendations. This test procedure is not equivalent to, and is not intended to replace, the hot-spot endurance test in IEC 61215-2. The safety aspects of partial shading of PV modules are covered by IEC 61730-2 MST 22 and IEC 61215-2 MQT 09.