IEC 60904-4:20 19作为IEC 60904-4:20 19 RLV提供，其中包含国际标准及其红线版本，显示了与上一版本相比技术内容的所有变化。IEC 60904-4:20 19设定了校准程序的要求，旨在按照IEC 60904-2的要求建立光伏(PV)参考器件与SI单位的可追溯性。本文件适用于用于测量自然或模拟阳光辐照度以量化PV器件性能的PV参考器件。许多关于PV的标准（例如IEC 60904-1和IEC 60904-3）要求使用PV参考器件。本文件是在考虑单结PV参考器件，特别是晶体硅的情况下编写的，但是它足够笼统地包括其他单结PV参考器件。junction technologies。第二版取消并取代了2009年出版的第一版。与上一版相比，此版本包括以下重大技术变更: 标准标题的修改； -将工作参考纳入可追溯链； -相对于SI更新WRR； -修订附件中的所有方法及其不确定性 -符号和公式与其他IEC标准的协调。

IEC 60904-4:2019 is available as IEC 60904-4:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.

IEC 60904-4:2019 sets the requirements for calibration procedures intended to establish the traceability of photovoltaic (PV) reference devices to SI units as required by IEC 60904-2. This document applies to PV reference devices that are used to measure the irradiance of natural or simulated sunlight for the purpose of quantifying the performance of PV devices. The use of a PV reference device is required in many standards concerning PV (e.g. IEC 60904-1 and IEC 60904-3). This document has been written with single-junction PV reference devices in mind, in particular crystalline silicon, but it is sufficiently general to include other single-junction technologies. This second edition cancels and replaces the first edition published in 2009. This edition includes the following significant technical changes with respect to the previous edition:
modification of standard title;
- inclusion of working reference in traceability chain;
- update of WRR with respect to SI;
- revision of all methods and their uncertainties in annex
- harmonization of symbols and formulae with other IEC standards.