scope:

This document provides guidelines for measurements of the maximum power (Pmax) output of single-junction photovoltaic (PV) modules and for reporting at standard test conditions (STC) in industrial production line settings. Such measurements typically: • Record current-voltage (I-V) data while illuminating the module with a solar simulator; • Are performed on 100 % of manufactured modules, in order to determine whether they meet nameplate requirements for various bins spanning different power output levels. This type of measurement is widespread and performed in high volume by PV module manufacturers worldwide. As it is desirable to have consistent measurement practices across the industry, this report describes the following features of such measurements: • Essential elements, in order to provide common understanding; • Common issues or complications; • Sources of error and uncertainty, including recommendations to minimize them. Understanding of Pmax measurement uncertainties is expected to be useful in application of other IEC documents, such as IEC 61215-1 and IEC 62941:2019, where Pmax tolerances and uncertainties have to be determined. Whenever possible, this report references specific IEC documents covering topics in more detail. Where no such documents exist, this report provides guidance and recommendations based on other publications relevant to the PV industry.