Photovoltaic (PV) modules are electrical devices designed for continuous outdoor exposure throughout their lifespan. Highly corrosive wet atmospheres, such as marine environments or locations near the ocean or other large saltwater bodies, can eventually cause permanent deterioration of some PV module components, impairing their function (corrosion of metallic parts, deterioration of protective coatings and some non-metallic materials such as plastics due to assimilation of salts). Temporary corrosive atmospheres also exist where salt is used to melt ice on streets and roads during winter periods.
The standard “IEC 61701 Photovoltaic (PV) modules - Salt fog corrosion test” published by the International Electrotechnical Commission (IEC) describes useful test methods for determining the resistance of different photovoltaic (PV) modules to corrosion caused by salt fog containing chlorine (such as sodium chloride, magnesium chloride). Details of all these tests are included in the following standards:
The bypass diode functionality test in this standard differs from the description given in the IEC 61215-2 standard. These have been combined in this standard to provide tools for evaluating potential failures that may occur in photovoltaic (PV) modules when operating in wet atmospheres with high dissolved salt (sodium chloride) concentrations. Depending on the specific nature of the surrounding atmosphere to which the module is exposed during actual operation, various test methods may be applied, as defined in the IEC 60068-2-52 standard. Guidance on determining the applicability of this standard and selecting an appropriate method is included in the standard annex (Annex A). This document is applicable to both flat plate photovoltaic (PV) modules and concentrator photovoltaic (PV) modules and assemblies.
For the purposes of this standard, the terms and definitions given in the IEC TS 61836 standard are valid.
Three identical samples of the photovoltaic (PV) module or assembly of interest are subjected to any of the test sequences given in the figures within the standard for non-concentrating or concentrating photovoltaics, respectively. As the figures show, one of these samples should be used as a control. The control sample should be used as a control each time the test samples are measured to evaluate the effect of the salt spray test. In the case of concentrating photovoltaics, different situations may arise for sample selection. For non-field-tuned focal point concentrating photovoltaic systems or modules, three modules are required to complete the test sequence shown in the figure. For field-tuned focal point concentrating photovoltaic systems or assemblies, three receivers (including secondary optical sections, if any) and three primary optical sections are required to complete the test sequence shown in the figure. A full description of the different types and components of concentrating photovoltaic modules and assemblies is contained in the IEC 62108 standard.
If a full-size sample is too large to fit into the environmental chambers required for salt fog testing, a smaller representative sample can be specially designed and manufactured for this test. The representative sample should be carefully designed to reveal similar failure mechanisms as the full-size sample, and the manufacturing process for the representative sample should be as similar as possible to that for the full-size samples. The fact that testing was done on representative samples and not on full-size samples should be reported in the test report. If the photovoltaic (PV) module is equipped with grounding means, the ground connection should be tested as part of the module.
After stabilization, tests are performed to characterize the PV module and verify that it was operational prior to salt fog exposure. After exposure, the samples are cleaned and allowed to recover. This sequence is then repeated and the bypass diode functional test is performed. All tests included in this standard are fully described in the referenced clauses of the listed IEC standards. The tests included in the figures should be performed in the order specified. In the case of concentrator photovoltaics, if some test procedures included in this standard cannot be applied to a particular design configuration, the manufacturer and the test organization should prepare a comparable test program based on the principles described in this standard. Any changes and deviations should be recorded and reported in detail.
Our organization, which has been trying to support businesses from every sector with its wide range of testing, measurement, analysis and evaluation studies for years, has a strong staff that closely follows the developments in the world in the field of science and technology and constantly improves itself. In this context, testing services in accordance with the "IEC 61701 Photovoltaic (PV) modules - Salt fog corrosion test" standard are also provided to businesses.
To get an appointment, to get more detailed information or to request an evaluation, you can ask us to fill in our form and reach you.
