Trina Solar has conducted stringent dynamic mechanical load testing (DML) of its 210 Vertex 670W module, comparing it with competitors’ single-glass 540W and dual-glass 535W modules in extreme environments based on International Electrotechnical Commission (IEC) standards. The testing demonstrated that the Vertex module delivered better performance in terms of DML reliability and, with the double-glass 210 mm Vertex also passing extreme 20,000 cycle, 20-fold testing, its DML reliability has been fully validated.
Based on the IEC TS 62782 standard, testing was carried out at the State Key Laboratory of PV Science and Technology. Generally, standard DML testing consists of 1,000 cycles (3-7 cycles per minute), with each applying a positive loading (front side) and negative loading (rear side) of 1,000Pa on the module tested. However, in extreme weather such as heavy snow, wind and hail, a module may rupture due to high pressure from mechanical loading, which would lead to moisture entry, cell cracks and corrosion and fatigue of welded joints, eventually resulting in module and system failure.
On this occasion, the extreme testing for the 210 Vertex module was carried out based on multi-fold standard DML.
The testing included two rounds as follows:
Round 1: the multi-fold DML testing was conducted based on a standard load of ±1,000Pa, with the appearance of the samples observed every 500 cycles.
With the single glass module secured by bolts to the crossbeam, perpendicular to the long side, the 540W unit showed cracks near the mounting holes after going through 3,000 DML cycles, while the 210 mm Vertex continued functioning as normal at the end of 7,000 cycles.
With the dual-glass framed module bolted to the crossbeam, parallel to the long side, the 540W unit showed cracks after 2,000 DML cycles while the Vertex continued operating normally after 3,500 cycles.
With the dual-glass framed module secured to the crossbeam by clamps, parallel to the long side, the appearance of the Vertex module remained intact after 20,000 cycles.
Round 2: the multi-fold DML testing was conducted based on a standard load of ±1,500Pa and the appearance of the samples was observed after every 200 cycles.
With the dual-glass framed module secured to the crossbeam by bolts, parallel to the long side, the 535W module failed at the end of 200 cycles, with cracks occurring near two mounting holes and another two mounting holes tearing completely, resulting in screws dropping out; in contrast, the 210 Vertex only had minor cracks around one mounting hole after 2,000 DML cycles.
With the dual-glass framed module secured to the crossbeam by clamps, parallel to the long side, the appearance of the Vertex 670W module remained intact after 20,000 cycles.
The two rounds of comparative testing once again demonstrated the outstanding capability of the 210 Vertex in resisting external mechanical stress.
Worldwide shipments of the 210 Vertex module now exceed 16GW.