SEMI PV84 - Test Method for Polymer Foil Dependent Discoloration of Silver Fingers on Photovoltaic Modules
This Standard was technically approved by the Photovoltaic Global Technical Committee. This edition was approved for publication by the global Audits and Reviews Subcommittee on March 19, 2018. Available at www.semiviews.org and www.semi.org in August 2018.
The purpose of this Standard is to standardize the accelerated evaluation method for discoloration of silver fingers on photovoltaic (PV) modules. The test is performed with designed mini module in a pressure cooker with moisture condensing or moisture saturated steam environment.
Pressure cooker test (PCT) is a highly accelerated test which employs high pressure, humidity and temperature under condensing conditions to accelerate moisture penetration into laminated mini modules.
The PV polymer foil suppliers, PV module manufactures and buyers, or any other party interested, can thus have common standards to test and select PV encapsulation materials for PV modules efficiently.
This test is used to evaluate the susceptibility and occurrence of discoloration of PV finger metallization. The influence of encapsulation materials used in PV modules such as ethylene-vinyl acetate (EVA), back sheet polymer foil or any other materials that protect crystalline Si cells in PV modules can be tested with this method.
Some cautions should be considered when performing this test and evaluating test results. Failure mechanisms, both internal (e.g., due to embrittlement of PET) and external (e.g., moisture ingress from non-sealed edge), may be produced which are not applicable to the intended application use conditions.
This Standard defines the specific testing methods, testing conditions and evaluation method for PV polymer foils.
Referenced SEMI Standards