TC 82 - Solar photovoltaic energy systems

IEC TS 62257-9-8:2025 provides baseline requirements for quality, durability and truth in advertising to protect consumers of off-grid renewable energy products. Evaluation of these requirements is based on tests described in IEC TS 62257-9-5. This document can be used alone or in conjunction with other international standards that address the safety and durability of components of off-grid renewable energy products.
This document applies to stand-alone renewable energy products having the following characteristics:
- The products are powered by photovoltaic (PV) modules or electromechanical power generating devices (such as dynamos), or are designed to use grid electricity to charge a battery or other energy-storage device for off-grid use. The requirements may also be appropriate as guidance for evaluating the quality of products with other power sources, such as thermoelectric generators.
- The peak power rating of the PV module or other power generating device is less than or equal to 350 W.
- The system evaluated includes all the loads (lighting, television, radio, fan, etc.) and load adapter cables that are sold or included as part of the kit or integrated into kit components.
- The PV module maximum power point voltage and the working voltage of any other components in the kit do not exceed 35 V. Exceptions are made for AC-to-DC converters that meet appropriate safety standards, and systems that include PV modules (or combinations of PV modules) with open-circuit voltage greater than 35 V that meet additional safety requirements beyond those assessed in IEC TS 62257-9-5.
This document includes provisions related to safety; however, it is not intended to be a comprehensive safety standard. In particular, this document is not intended to be used as an alternative to safety standards such as IEC 62368-1 or the IEC 60335 series for appliances such as radios and televisions that are included with stand-alone renewable energy products. Nor is it intended to replace the safety requirements of IEC 62281 or UN 38.3 for battery safety during transport, or safety requirements of IEC 61730-1 and IEC 61730-2 for PV modules intended for use outside the context of stand-alone renewable energy products.

IEC TS 62257-9-5:2024 provides support and strategies for institutions involved in rural electrification projects. It documents technical approaches for designing, building, testing, and maintaining off-grid renewable energy and hybrid systems with AC nominal voltage below 500 V, DC nominal voltage below 750 V and nominal power below 100 kVA.
The purpose of this document is to specify laboratory test methods for evaluating the quality assurance of stand-alone renewable energy products. This document is specifically related to renewable energy products that are packaged and made available to end-use consumers at the point of purchase as single, stand-alone products that do not require additional system components to function.
This document establishes the framework for creating a product specification, the basis for evaluating quality for a particular context. Product specifications include minimum requirements for quality standards and warranty requirements.
This document applies to stand-alone renewable energy products having the following characteristics: This document was written primarily for off-grid renewable energy products with batteries and PV modules with DC system voltages not exceeding 35 V and peak power ratings not exceeding 350 W. This document includes provisions related to safety; however, it is not intended to be a comprehensive safety standard. In particular, this document is not intended to be used as an alternative to safety standards such as IEC 62368-1 or IEC 60335 (all parts) for appliances such as radios and televisions that are included with stand-alone renewable energy products

IEC TS 60904-1-2:2024 describes procedures for the measurement of the current-voltage (I-V) characteristics of single junction bifacial photovoltaic devices in natural or simulated sunlight. It is applicable to encapsulated solar cells, sub-assemblies of such cells or entire PV modules. For measurements of I-V characteristics of non-encapsulated solar cells, IEC TS 63202-3 applies.
The requirements for measurement of I-V characteristics of standard (monofacial) PV devices are covered by IEC 60904-1, whereas this document describes the additional requirements for the measurement of I-V characteristics of bifacial PV devices.
This second edition cancels and replaces the first edition published in 2019. This edition includes the following significant technical changes with respect to the previous edition:
a) The scope has been updated and refers to IEC TS 63202-3 for the measurement of non‑encapsulated solar cells.
b) The requirements for the non-uniformity of irradiance have been updated and now refer to classifications introduced in IEC 60904-9.
c) The requirement for non-irradiated background has been revised.
d) Spectral mismatch corrections are no longer mandatory, unless required by another standard. Spectral mismatch would have to be considered in the measurement uncertainty.
e) The requirement regarding the calculation of bifaciality has been modified: Equivalent irradiance shall not be calculated based on the minimum bifaciality value between ISC and Pmax, but on the bifaciality of ISC.

IEC 62788-1-1:2024 defines test methods and reporting requirements for characteristics (optical, mechanical, electrical, thermal, and chemical) of non-rigid polymeric materials (e.g., poly(ethylene-co-vinyl acetate), EVA) intended for use in terrestrial photovoltaic (PV) modules as polymeric encapsulants.
The test methods in this document define how to characterize encapsulant materials in a manner representative of how they will be used in the module, which includes combination with other components such as frontsheets, backsheets, adhesives, edge seals, or glass.The methods described in this document support and supplement the safety- and performance-related tests defined on the PV module level, as defined in IEC 61730-2 and IEC 61215-1. This document also defines test methods for general assessment of material characteristics of polymeric encapsulants.
The test methods described in this document may be used for the purposes of: datasheet reporting (aiding module design or material research and development); process and manufacturing control (e.g., incoming or outgoing inspection); application in module safety and design type qualification protocols; or reliability and durability study/standards development

IEC 62788-7-3:2022 defines the test methods that can be used for evaluating the abrasion of materials and coatings in photovoltaic modules or other solar devices. This document may be applied to components on the incident surface (including coatings, frontsheet, and glass) as well as the back surface (including backsheets or back glass). This document is intended to address abrasion of PV module surfaces and any coatings present using representative specimens (e.g. which can be centimetres in size); the methods and apparatus used here can also be used on PV module specimens (e.g. meters in size).

IEC TS 62788-2:2024 defines test methods and datasheet reporting requirements for safety and performance-related properties (mechanical, electrical, thermal, optical, chemical) of non‑rigid polymeric materials intended for use in terrestrial photovoltaic modules as polymeric front- and backsheets. The test methods in this document define how to characterize front- and backsheet materials and their components in a manner representative of how they will be used in the module, which eventually includes combination with other matched components such as encapsulants or adhesives. Results of testing described in this document are called by IEC 62788-2-1 for safety qualification of polymeric front- and backsheets on component level and support the safety and performance-related tests defined on the PV module level as defined in the series IEC 61730 (for safety) and IEC 61215 (for performance). This document also defines test methods for assessing inherent material characteristics of polymeric front- and backsheets or their components, which can be required in datasheet reporting or can be useful in the context of product development or design of PV modules.
This second edition cancels and replaces the first edition published in 2017. This edition includes the following significant technical changes with respect to the previous edition:
a) With revision of IEC 61730-1 the requirements for the polymeric front- and backsheet have been moved from IEC 61730-1 into IEC 62788-2-1. This is reflected accordingly.
b) The tensile testing method has been refined based on findings of round robin tests, including updated drawings.
c) A thermal pre-exposure method has been introduced to be equivalent to the thermal effects of a "lamination" cycle. This pre-exposure defines the "fresh" state of the front- or backsheet in final application for evaluation of changes in ageing tests. For practical reasons, an oven exposure has been defined as an equivalent test.
d) The multiple functions of the lamination protrusion test (previously DTI test) have been clarified, to identify and measure RUI layer thickness as well as to identify layers for which the comparative tracking index (CTI) needs to be determined. Also the content of IEC 62788-2-1 has been updated, by which the lamination protrusion test and MST 04 are additionally set in perspective to each other via engineering judgement.
e) The DC breakdown voltage test method has been updated and the option to perform a withstand voltage test has been added (to reduce the required measurement voltage). The correction of DC breakdown voltage ( ) measurements, needed in the presence of non‑RUI layers and after the lamination protrusion test, has been defined more precisely.
f) Details for thickness measurement have been added (engineered surface roughness due to embossing).
g) The adhesion test methods have been reviewed and updated. The single cantilevered beam test has been added. Figures have been updated to align with IEC 62788-1-1.
h) The thermal failsafe test has been added as a test method based on discussion in the parallel project for IEC 62788-2-1. The test method offers a single temperature-point evaluation to include elongation at break to the thermal endurance evaluation.
I) A sequential UV/TC test ("solder bump test") has been added.

IEC TS 62788-8-1:2024 defines test methods and datasheet reporting requirements for key characteristics of ECA used in photovoltaic modules, involving mechanical characteristics, adhesive characteristics, electrical characteristics, thermal characteristics, etc.
The object of this document is to offer a standard test procedure to ECA manufacturers for product design, production and quality control, and to PV module manufacturers for the purpose of material screening, material inspection, process control, and failure analysis.
This document is intended to be applied to ECA used in solar PV modules. For non-conductive adhesives or tapes used in PV modules, the applicable test methods except for electrical characteristics in this document may be used.

IEC 62548-1:2023 sets out design requirements for photovoltaic (PV) arrays including DC array wiring, electrical protection devices, switching and earthing provisions. The scope includes all parts of the PV array and final power conversion equipment (PCE), but not including energy storage devices, loads or AC or DC distribution network supplying loads. The object of this document is to address the design safety requirements arising from the particular characteristics of photovoltaic systems. This document also includes extra protection requirements of PV arrays when they are directly connected with batteries at the DC level.
This first edition cancels and replaces IEC 62548 published in 2016. This edition includes the following significant technical changes with respect to the previous edition:
a) Revised provisions for systems including DC to DC conditioning units.
b) Revision of mounting structure requirements.
c) Revised cable requirements.
d) Revision of Clause 6 on safety issues which includes provisions for protection against electric shock including array insulation monitoring and earth fault detection.
e) Revision of 7.2.7 and 7.3 with respect to isolation means.
f) Provisions for use of bifacial modules and modules mounted in non-optimal orientations.
g) New Annex F containing: KI factor calculations for bifacial and non-optimally oriented systems; anti-PID equipment and arc flash.

IEC TS 62915:2023 sets forth a uniform approach to maintain type approval, design and safety qualification of terrestrial PV modules that have undergone or will undergo modification from their originally assessed design. This document addresses two types of PV module technologies, wafer-based technologies (WBT) and monolithically-integrated (MLI) thin-film based technologies.
This document lists typical modifications and the resulting requirements for retesting based on the different test standards. It provides assistance; at some level, engineering judgement may be needed.
This publication contains attached files in the form of xls document. These files are intended to be used as a complement and do not form an integral part of the publication.
This second edition cancels and replaces the first edition published in 2018. This edition includes the following significant technical changes with respect to the previous edition:
- Prior references to specific process-related changes to PV modules have been removed in this edition and replaced with a general requirement to ensure that a consistent quality management system is in place per IEC 62941
- References to IEC 61215 and IEC 61730 have been updated to the latest editions (2021 and 2023 respectively)
- Retest requirements with respect to new added tests such as cyclic (dynamic) mechanical load (MQT 20) and potential-induced degradation (MQT 21) are addressed in this edition
- Retest requirements for IEC 61215 and IEC 61730 have been separated for the sake of clarity
- A comprehensive matrix table summarizing all the retest requirements for each possible change in material(s) or design modification is provided in this edition
- References to component level standards, namely IEC 62788-1 series and IEC 62788-2 series, are included in this edition to address changes that could be made to the critical sub-components going into new PV module constructions
- Crystalline silicon and thin film references have been updated to be consistent with nomenclature in the updated IEC 61215 and IEC 61730 standards; namely, wafer-based technology (WBT) and monolithically integrated (MLI) thin film PV modules
- In this edition, 4.3 which addresses retest requirements for MLI thin film PV modules has been truncated and simplified by removing redundant sections that are identical with the subclauses in 4.2
Guidance for retesting modules according to IEC TS 63126, “Guidelines for qualifying PV modules, components and materials for operation at high temperatures” has been added to this edition.
- In this edition, requirements have been added for changes affecting system compatibility with variants of the same model
The contents of the corrigendum 1 of July 2024 have been included in this copy.

IEC 61730-1:2023 specifies and describes the fundamental construction requirements for photovoltaic (PV) modules in order to provide safe electrical and mechanical operation. Specific topics are provided to assess the prevention of electrical shock, fire hazards, and personal injury due to mechanical and environmental stresses. This document pertains to the particular requirements of construction. IEC 61730-2 defines the requirements for testing. Modules with modified construction are qualified as described in IEC TS 62915.
This document lays down requirements for terrestrial PV modules suitable for long-term operation in open-air climates with 98th percentile module operating temperatures of 70 °C or less. Guidelines for modules to be used at higher operating temperatures are described in IEC TS 63126.
This document is intended to apply to all terrestrial flat plate module materials, such as crystalline silicon module types as well as thin-film modules.
This document defines the basic requirements for various applications of PV modules, but it cannot be considered to encompass all national or regional codes.

IEC 61730-2:2023 lists the tests a PV module is required to fulfil for safety qualification. This document applies for safety qualification only in conjunction with IEC 61730-1. The objective of this document is to provide the testing sequence intended to verify the safety of PV modules whose construction has been assessed by IEC 61730-1. The test sequence and pass criteria are designed to detect the potential breakdown of internal and external components of PV modules that would result in fire, electric shock, and/or personal injury. This document defines the basic safety test requirements and additional tests that are a function of the PV module end-use applications. The additional testing requirements outlined in relevant ISO documents, or the national or local codes which govern the installation and use of these PV modules in their intended locations, are considered in addition to the requirements contained within this document.
The content of the corrigendum 1 (2024-10) has been included in this copy.

IEC 62788-2-1:2023 specifies the safety requirements for flexible polymeric front- and backsheet constructions, which are intended for use as relied-upon insulation in photovoltaic (PV) modules. The specifications in this document define the specific requirements of polymeric front- or backsheet constructions on the component level and cover mechanical, electrical, visual and thermal characterization in an unexposed state and/or after ageing.
This document covers class II and class 0 modules, as defined in IEC 61730-1. Class III modules are out of scope. This document provides the requirements for qualification of front- and backsheets to be used in module safety qualification according to IEC 61730-1. Test method descriptions are provided in IEC TS 62788-2, along with additional characterization methods useful for performance or quality assurance.

IEC 60904-2:2023 gives requirements for the classification, selection, packaging, marking, calibration and care of photovoltaic reference devices. This document applies to photovoltaic (PV) reference devices that are used to measure the irradiance of natural or simulated sunlight for the purpose of quantifying the electrical performance of photovoltaic devices (cells, modules and arrays). It does not cover photovoltaic reference devices for use under concentrated sunlight. This fourth edition cancels and replaces the third edition published in 2015. This edition includes the following significant technical changes with respect to the previous edition:
a) added calibration procedures for calibrating PV devices at maximum power by extending the respective Clauses 12 and 13;
b) revised requirements for mandatory measurement of spectral responsivity, temperature coefficients and linearity, depending on usage and allowing some measurements on equivalent devices;
c) revised requirements for built-in shunt resistor;
d) added requirements for traceability of calibration explicitly.

IEC 63027:2023 applies to equipment used for the detection and optionally the interruption of electric DC arcs in photovoltaic (PV) system circuits. The document covers test procedures for the detection of series arcs within PV circuits, and the response times of equipment employed to interrupt the arcs.
The document defines reference scenarios according to which the testing is conducted. This document covers equipment connected to systems not exceeding a maximum PV source circuit voltage of 1 500 V DC. This document provides requirements and testing procedures for arc-fault protection devices used in PV systems to reduce the risk of igniting an electrical fire.

IEC TS 63202-3:2023 describes procedures for the measurement of current-voltage (I-V) characteristics of crystalline silicon bifacial photovoltaic (PV) cells for both laboratory and mass production applications.
This document is intended to be used for measurement of individual unencapsulated bifacial PV cells, in addition to the requirements described in IEC 60904-1 and differentiating from IEC TS 60904-1-2 which is more applicable to encapsulated PV device. Specific requirements on bifacial reference cells and calibration of solar simulators are also defined to provide useful guidance for the proposed methods.

IEC TS 63397:2022 defines additional testing requirements for modules deployed under applications or in environments where PV modules are likely to be exposed to the impact of hailstones leading to higher stress beyond the scope of the IEC 61215 series. This document aims to assist in the selection of modules for deployment in specific regions that have a higher risk of hail damage and to provide tools for improving module design.
The contents of the corrigendum of July 2023 have been included in this copy.

IEC 60904-5:2011 describes the preferred method for determining the equivalent cell temperature (ECT) of PV devices (cells, modules and arrays of one type of module), for the purposes of comparing their thermal characteristics, determining NOCT (nominal operating cell temperature) and translating measured I-V characteristics to other temperatures. The main technical changes with regard to the previous edition are as follows:
- added method on how to extract the input parameters;
- rewritten method on how to calculate ECT;
- reworked formulae to be in line with IEC 60891.

IEC TS 62257-100:2022 introduces the entire series regarding off-grid renewable energy and hybrid products and systems most commonly used for rural applications and access to electricity. This document provides a guide for facilitating the reading and the use of the IEC 62257 series for setting up off-grid electrification in developing countries or in developed countries, the only difference being the level of service and the needed quantity of energy that the customer can afford.
This document outlines the organization of documents within the updated IEC 62257-xxx series published in 2022 and later, including utilization of a new 3-digit part numbering scheme, grouped into topics and subtopics.

IEC TS 62788-6-3:2022 describes the single cantilevered beam (SCB) test, useful for characterizing adhesion in photovoltaic (PV) modules. This document offers a generalized method for performing the test, with the expectation that best practices for utilizing this test method will be developed for specific applications.
This document provides a method for measuring the adhesion energy of most interfaces within the photovoltaic (PV) module laminate. This method provides a measure of adhesive energy, via the critical energy release rate, and so is more useful for comparing adhesion of different specimen types; e.g. different materials, module or coupon samples, or materials before and after stress exposure.

IEC TS 63209-2:2022 includes a menu of tests to use for evaluation of the long-term reliability of materials used as backsheets and encapsulants in PV modules. It is intended to provide information to supplement the baseline testing defined in IEC 61215 and IEC 61730, which are qualification tests with pass-fail criteria. used for reliability analysis and is not intended to be used as a pass-fail test procedure. This document addresses polymeric materials in the crystalline silicon module laminates, specifically backsheets and encapsulants in Glass/Glass or Glass/Backsheet modules. The included environmental stress tests are intended to cause degradation that is most relevant to field experience, but these may not capture all failure modes which may be observed in various locations.

IEC TS 63342:2022 is designed to assess the effect of light induced degradation at elevated temperatures (LETID) by application of electrical current at higher temperatures. In this document, only the current injection approach for the detection of LETID is addressed.
This document does not address the B-O and Iron Boron (Fe-B) related degradation phenomena, which already occur at room temperatures under the presence of light and on much faster time scales. The proposed test procedure can reveal sample sensitivity to LETID degradation mechanisms, but it does not provide an exact measure of field observable degradation.

IEC 62759-1:2022 describes methods for the simulation of transportation of complete package units of modules and combined subsequent environmental impacts.
This second edition cancels and replaces the first edition published in 2015. This edition includes the following significant technical changes with respect to the previous edition:
a. Cancellation of tests and references to relevant standards for CPV.
b. Deletion of different classes for PV modules.
c. Deletion of requirement for minimum 10 modules per shipping unit.
d. Implementation of stabilization as intermediate measurement.
e. Addition of pass/fail criteria.
f. Change of requirements for retesting.
g. Change of number of cycles in dynamic mechanical load test.

IEC TS 63202-4:2022 describes procedures for measuring the light and elevated temperature induced degradation (LETID) of crystalline silicon photovoltaic (PV) cells in simulated sunlight. The requirements for measuring initial light induced degradation (LID) of crystalline silicon PV cells are covered by IEC 63202-1, where LID degradation risk of PV cells under moderate temperature and initial durations within termination criteria of 20 kWh·m-2 are evaluated. The procedures described in this document are to evaluate the degradation behaviour of PV cells under elevated temperature and longer duration of light irradiation. The procedures described in this document can be used to detect the LETID risks of PV cells [2],[3] and to judge the effectiveness of LETID mitigation measures, e.g. quick test for production monitoring, thus helping improve the energy yield of PV modules.

IEC TS 63265:2022 outlines methods that can be utilized to ensure reliability throughout the PVPS project phases. It is derived from a management motivation for long lasting and cost-effective energy performance, energy production, secure production and revenue, and safe function. The application of reliability practices in this document is designed to be practical and reduce the costs of unreliability. This document further identifies and defines a normative minimum set of processes and tools to meet the requirements of this document.
Key objectives of this document are to inform users of reliability tools and assessment methods (historic, predictive, and analytical) that can satisfy the stakeholders needs for dependable PV Power System (PVPS) operation. This document provides a fundamental process for ensuring reliability needs can be understood and met. IEC TS 63019 addresses availability which is a higher-level metric that combines reliability and maintainability, and it complements this document as a key normative standard. It should be used in combination with this document.

IEC 62108:2022 specifies the minimum requirements for the design qualification and type approval of concentrator photovoltaic (CPV) modules and assemblies suitable for long-term operation in general open-air climates as defined in IEC 60721-2-1. The object of this test document is to determine the electrical, mechanical, and thermal characteristics of the CPV modules and assemblies and to show, as far as possible within reasonable constraints of cost and time, that the CPV modules and assemblies are capable of withstanding prolonged exposure in climates described in the scope.

IEC TS 62804-2:2022 defines apparatus and procedures to test and evaluate the durability of photovoltaic (PV) modules to power loss by the effects of high voltage stress in a damp heat environment, referred to as potential-induced degradation (PID). This document defines a test method that compares the coulomb transfer between the active cell circuit and ground through the module packaging under voltage stress during accelerated stress testing with the coulomb transfer during outdoor testing to determine an acceleration factor for the PID.
This document tests for the degradation mechanisms involving mobile ions influencing the electric field over the semiconductor absorber layer or electronically interacting with the films such that module power is affected.

IEC TS 63106-2:2022 provides recommendations for Low Voltage (LV) DC power simulators used for testing photovoltaic (PV) power conversion equipment (PCE) to utility interconnection or PV performance standards. This document primarily addresses DC power simulators used for testing of grid-interactive PCE, also referred to as grid-connected power converters (GCPCs). It also addresses some uses of DC power simulators for testing stand-alone and multi-mode PCEs.

IEC 61215-1-3:2021 lays down requirements for the design qualification of terrestrial photovoltaic modules suitable for long-term operation in open-air climates. The useful service life of modules so qualified will depend on their design, their environment and the conditions under which they are operated. Test results are not construed as a quantitative prediction of module lifetime. This document is intended to apply to all thin-film amorphous silicon (a-Si; a-Si/µc-Si) based terrestrial flat plate modules. As such, it addresses special requirements for testing of this technology supplementing IEC 61215-1:2021 and IEC 61215-2:2021 requirements for testing. This second edition cancels and replaces the first edition of IEC 61215-1-3, issued in 2016. This edition includes the following significant technical changes with respect to the previous edition:
a. A cyclic (dynamic) mechanical load test (MQT 20) added.
b. A test for detection of potential-induced degradation (MQT 21) added.
c. A bending test (MQT 22) for flexible modules.

IEC 61215-1-2:2021 lays down requirements for the design qualification of terrestrial photovoltaic modules suitable for long-term operation in open-air climates. The useful service life of modules so qualified will depend on their design, their environment and the conditions under which they are operated. Test results are not construed as a quantitative prediction of module lifetime. This document is intended to apply to all thin-film CdTe based terrestrial flat plate modules. As such, it addresses special requirements for testing of this technology supplementing IEC 61215-1:2021 and IEC 61215-2:2021 requirements for testing. This document defines PV technology dependent modifications to the testing procedures and requirements per IEC 61215-1:2021 and IEC 61215-2:2021. This second edition cancels and replaces the first edition of IEC 61215-1-2, issued in 2016. This edition includes the following significant technical changes with respect to the previous edition:
a. A cyclic (dynamic) mechanical load test (MQT 20) added.
b. A test for detection of potential-induced degradation (MQT 21) added.
c. A bending test (MQT 22) for flexible modules added.

IEC 61215-1-4:2021 lays down requirements for the design qualification of terrestrial photovoltaic modules suitable for long-term operation in open-air climates. The useful service life of modules so qualified will depend on their design, their environment and the conditions under which they are operated. Test results are not construed as a quantitative prediction of module lifetime. This document is intended to apply to all thin-film Cu(In,Ga)(S,Se)2 based terrestrial flat plate modules. As such it addresses special requirements for testing of this technology supplementing IEC 61215-1:2021 and IEC 61215-2:2021 requirements for testing. This second edition cancels and replaces the first edition of IEC 61215-1-4, issued in 2016. This edition includes the following significant technical changes with respect to the previous edition:
a. A cyclic (dynamic) mechanical load test (MQT 20) added.
b. A test for detection of potential-induced degradation (MQT 21) added.
c. A bending test (MQT 22) for flexible modules added.
This standard is to be read in conjunction with IEC 61215-1:2021 and IEC 61215-2:2021.

IEC TS 63109:2022 specifies a method to measure the diode ideality factor of photovoltaic cells and modules by quantitative analysis of electroluminescence (EL) images. This document provides a definition of the term diode ideality factor n, as the inverse of increment ratio of natural logarithm of current as a function of applied voltage, which is related to the fill factor FF, and is useful as an effective indicator to represent the output efficiency of photovoltaic cells and modules with the other key parameters open circuit voltage Voc and short circuit current Isc.

IEC TS 62257-7-2:2022 applies to all small wind turbines (SWTs) with a swept area smaller than or equal to 200 m2, and designed for supplying electrical power to isolated sites used in systems as described in IEC TS 62257-2.
This document is not an exhaustive resource for the design, installation, operation or maintenance of small wind turbines and wind power systems, but is more focused on recommendations to provide strategies on selection and criteria which may affect the use of a small wind power system (SWPS) in a rural electrification project.
The aim of this document is to provide users with the appropriate levels of reliability and safety of the equipment during its estimated service lifespan.

IEC TS 63349-2:2022 defines operation modes of photovoltaic direct-driven appliance (PVDDA) controllers and describes one example of a graphic display. The graphic display is an interface to PVDDA users, which uses easily understood graphics to show a real-time operation mode, such as what equipment is installed, controlled and monitored in the system, which equipment is generating power and how much it generates, and which equipment is consuming power and how much it consumes. This helps with user’s interest, knowledge, planning on renewable energy usage.

IEC 62788-5-1:2020 provides procedures for standardized test methods for evaluating the properties of materials designed to be used as edge seals. When modules are constructed with impermeable (or extremely low permeability) front- and backsheets designed to protect moisture-sensitive photovoltaic (PV) materials, there is still the possibility for moisture to get in from the sides. The test methods described in this document are intended to be used to standardize the way edge seals are evaluated. Only some of these tests are applied for IEC 61215 and IEC 61730, and that status depends on the specific design.

IEC 62093:2022 lays down IEC requirements for the design qualification of power conversion equipment (PCE) suitable for long-term operation in terrestrial photovoltaic (PV) systems.
This document covers electronic power conversion equipment intended for use in terrestrial PV applications. The term PCE refers to equipment and components for electronic power conversion of electric power into another kind of electric power with respect to voltage, current, and frequency. This document is suitable for PCE for use in both indoor and outdoor climates as defined in IEC 60721-3-3 and IEC 60721-3-4. Such equipment may include, but is not limited to, grid-tied and off-grid DC-to-AC PCEs, DC-to-DC converters, battery charger converters, and battery charge controllers. This document covers PCE that is connected to PV arrays that do not nominally exceed a maximum circuit voltage of 1 500 V DC.
This second edition cancels and replaces the first edition published in 2005. This edition includes the following significant technical changes with respect to the previous edition:
a. Title modified.
b. This edition focusses on the design qualification of power conversion electronics (PCE), and eliminates the clauses associated with qualification testing of other balance of system components.
c. While many clause titles remain the same as the first edition, substantial changes have been made.
d. Whereas the first edition establishes requirements for the design qualification of balance-of-system components used in terrestrial photovoltaic (PV) systems, this edition is limited to power conversion equipment.
e. The test protocols have been changed.

IEC TS 63202-2:2021 specifies methods to detect and examine defects on bare crystalline silicon (c-Si) solar cells by means of electroluminescence (EL) imaging with the cell being placed in forward bias. It firstly provides guidelines for methods to capture electroluminescence images of non-encapsulated c-Si solar cells. In addition, it provides a list of defects which can be detected by EL imaging and provides information on the different possible methods to detect and differentiate such defects.

IEC TS 63217:2021 provides a test procedure for evaluating the performance of Over Voltage Ride-Through (OVRT) functions in inverters used in utility-interconnected photovoltaic (PV) systems.
This document is most applicable to large systems where PV inverters are connected to utility high voltage (HV) distribution systems. However, the applicable procedures may also be used for low voltage (LV) installations in locations where evolving OVRT requirements include such installations, e.g. single-phase or 3-phase systems. This document is for testing of PV inverters, though it contains information that may also be useful for testing of a complete PV power plant consisting of multiple inverters connected at a single point to the utility grid. It further provides a basis for utility-interconnected PV inverters numerical simulation and model validation.

IEC 60891:2021 defines procedures to be followed for temperature and irradiance corrections to the measured I-V (current-voltage) characteristics (also known as I-V curves) of photovoltaic (PV) devices. It also defines the procedures used to determine factors relevant to these corrections. Requirements for I-V measurement of PV devices are laid down in IEC 60904-1 and its relevant subparts.
This third edition cancels and replaces the second edition published in 2009. This edition includes the following significant technical changes with respect to the previous edition:
- adds guidance on which correction procedure shall be used depending on application;
- introduces translation procedure 4 applicable to c-Si technologies with unknown temperature coefficients;
- introduces various clarifications in existing procedures to improve measurement accuracy and reduce measurement uncertainty;
- adds an informative annex for supplementary methods that can be used for series resistance determination.
The content of the corrigendum 1 (2024-10) has been included in this copy.

IEC TS 63163:2021 is intended to apply to terrestrial modules for consumer applications for outdoor operation shorter than those qualified to IEC 61215. The useful service life of modules so qualified depends on their design, their environment and the conditions under which they are operated. This document classes those PV modules into Category 1, Category 2, and Category 3 with respectively low, medium and high expected outdoor exposure. This specification is intended to qualify the PV portion of these devices. It may, however, be used as a basis for testing such PV modules, but does not qualify the electronic portion. The purpose of the test sequence is to determine the electrical, thermal, and mechanical durability characteristics of the module, and to show that the module is capable of withstanding outdoor exposure for different outdoor durations designated as “low”, “medium”, and “high”. Mobile and attached applications are considered to require lower mechanical durability than portable applications, which are more prone to mechanical damage.