BS EN IEC 62790:2020

What is BS EN IEC 62790 about? 

BS EN IEC 62790 is an international safety standard that deals with the security of the equipment used in photovoltaic modules.  

BS EN IEC 62790 describes safety requirements, constructional requirements and tests for junction boxes up to 1 500 V DC for use on photovoltaic modules in accordance with class II of IEC 61140:2016. 

BS EN IEC 62790 applies also to enclosures/junction boxes mounted on PV modules containing electronic circuits for converting, controlling, monitoring or similar operations. Additional requirements concerning the relevant operations are applied under consideration of the environmental conditions of the PV-modules.  

Note 1: BS EN IEC 62790 does not apply to the electronic circuits of these devices, for which other IEC standards apply. 

Note 2: BS EN IEC 62790 can be used as a guideline in photovoltaic systems, for junction boxes in accordance with classes 0 and III of IEC 61140:2016. 

Who is BS EN IEC 62790 for? 

BS EN IEC 62790 on junction boxes for photovoltaic modules 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 62790? 

The junction box is the least looked at but proves to be an important element of the solar panel system. They are pre-installed on the back of a photovoltaic module and are used for connecting the panels. 

BS EN IEC 62790 gives you requirements and recommendations for the junction boxes for photovoltaic modules that have a simple, but important role, that is, containing all the electric components of photovoltaic module and protecting them from the environment. Also, junction boxes enclose the wires/cables that are connected to diodes inside them, providing an easy way to link panels together. 

BS EN IEC 62790 helps solar developers and designers in building up junction boxes, by providing them with the construction requirements for photovoltaic modules. It also helps the module companies to work out the security features during manufacturing the junction boxes as it informs about the safety requirements as well as test procedures to ensure high efficiency and reliability of the junction boxes for photovoltaic modules.  

What’s changed since the last update? 

BS EN IEC 62790:2020 supersedes BS EN 62790:2015, which is withdrawn. 

BS EN IEC 62790:2020 includes the following changes: 

• Modifications in normative references and terms and definitions, improvement of declaration of categories for junction boxes, clarification for ambient temperature 
• Addition of requirement to provide information concerning RTE/RTI or TI, reference to IEC 62930 instead of EN 50618, the addition of "Functional insulation" in Table 1, the addition of "Distance through cemented joints" in Table 3 
• Correction of procedure of a process to categorize material groups (deletion of PTI), the requirement for approval of RTE/RTI or TI for insulation parts, change of requirements concerning electrochemical potential, clarification for IP-test  
• Addition of test voltage for cemented joints, the addition of detailed description on how to prepare the test sample for the thermal cycle test  
• New test procedure for bypass diode thermal test (5.3.18) in accordance with MQT 18.1 of IEC 61215-2:2016, the new test procedure for reverse overload current test, new figure 1 for thermal cycle test.