BS EN IEC 60904-10:2020

What is BS EN IEC 60904‑10 about? 

BS EN IEC 60904‑10 is a part of multi-series standard IEC 60904 that describes the procedures to measure the dependence of any electrical parameter (Y) of a photovoltaic (PV) device with respect to a test parameter (X). It determines the degree at which this dependence is close to an ideal linear (straight-line) function.  

BS EN IEC 60904‑10 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.  

BS EN IEC 60904‑10 gives the procedures to determine the deviation of the Y(X) dependence from the linear (straight-line) function are described in Clause 6 (measurements under natural sunlight and with solar simulator), Clause 7 (differential spectral responsivity measurements) and Clause 8 (measurements via two-lamp and N-lamp method). Data analyses to determine the deviations from the linear function are given in Clause 9. 

Note 1: The measurement methods described herein apply to all PV devices, with some caution to be used for multi-junction PV devices. 

Note 2: The principles described in BS EN IEC 60904‑10 can be applied to any other test parameter with proper adjustment of the procedure used to vary the parameter itself. 

Who is BS EN IEC 60904‑10 for? 

BS EN IEC 60904‑10 on linear dependence and linearity measurements of PV devices is useful for: 

• Manufacturers and suppliers of photovoltaic (PV) devices 
• Dealers and importers of photovoltaic (PV) devices 
• Testing houses/ service providers of photovoltaic (PV) devices 
• Entities dealing with photovoltaic (PV) devices 

Why should you use BS EN IEC 60904‑10? 

Performance evaluations of PV modules and systems, as well as performance translations from one set of temperature and irradiance to another, frequently rely on the use of linear equations. BS EN IEC 60904‑10 lays down the requirements for linear dependence test methods, data analysis, and acceptance limits of results to ensure that these linear equations will give satisfactory results. It also prescribes you the requirements, that give the range of the temperature and irradiance over which the linear equations may be used in order to evaluate the test parameters accurately.  

BS EN IEC 60904‑10 also gives you a procedure on how to correct for deviations of the short-circuit current ISC from the ideal linear dependence on irradiance (linearity) for PV devices, regardless of whether they are classified linear or non-linear.  

What’s changed since the last update? 

BS EN IEC 60904‑10:2020 supersedes BS EN 60904‑10:2010, which is withdrawn. 

BS EN IEC 60904‑10:2020 includes the following changes: 

• Modification of title, the inclusion of an Introduction explanatory of the changes and the reasoning behind them, the inclusion of a new Clause Terms and Definitions (Clause 3) 
• Explicit definition of the equivalent sample (Clause 4), technical revision of the apparatus (Clause 5), of the measurement procedures (Clause 6 to Clause 8), and of the data analysis (Clause 9) 
• Introduction of specific data analysis for the two-lamp method, making it fully quantitative, the addition of extended version called N-lamp method 
• Modification of the linearity assessment criterion with the inclusion of a formula 
• Revision of the requirements for the report (Clause 10)