DEFECTS OF SOLAR PANELS AND SOLUTIONS TO TEST ITS QUALITY

Oxidation, broken cells, humidity, bad fixing… manufacturing defects of the solar panels and the damage that can occur during transportation or installation are many. To pay for it is the quality of the solar panels, which is the first and the most important parameter to determine the value (economic) of the panels themselves. In addition to classic cracks of photovoltaic cells, we can divide the problems into 8 macro-groups, listed below in detail:

1. Snail Trail Effects→ broken celles, oxidation, power loss do to breakage, transportation/installation breakage;
2. Lamination Problem→ bubble in lamination, humidity inside, delamination of module, cells oxidation, insulation problem;
3. I.D.– Power Induced Degradation → Cells no PID-Free, poor EVA insulation, high power loss after 1-2 years, poor F.F.;
4. Yellowing of plastic material→ EVA Yellowing, back-sheet yellowing, scotch yellowing;
5. Yellowing on the ribbon→ ribbo yellowing, flux yellowing;
6. Bad soldering→ Poor welding process, wrong temperature setting, no tin during welding, wrong thickness of ribbon;
7. J-Box application→ Poor raw material, bad contact, wrong diode, wrong silicone curing;
8. Montage and transport→ Glass breakage, bad fixing, cells breakage

The only method to guarantee the maximum solar panels quality is to carry out continuous monitoringand verification during the entire production process, from raw material control to the I-V measurement at the end of the line. In particular, we at Ecoprogetti suggest to put an extreme attention to the certification of materials, the definition of internal procedures, the use of instruments and tools proper for monitoring the quality of the solar panels. Lets see some of the main instruments and test procedures for this type of investigation.

TEST AND PROCEDURES TO MEASURE SOLAR PANELS QUALITY

The main test that is worth mentioning in this article are primarily the “pull test” under lacing. It is a so-called destructive test, which tests the quality of welding “ripping off” the ribbon from the cell and assessing the strength and consistency of adherence. Also the electroluminescence is very important in the various stages of processing, as well as the gel content test for the check of the rolling quality. Last fundamental test to check the solar panels quality is the measurement of I-V curve at the end of the line, valid to control the accuracy of your measurements, but also to check the power loss of modules installed on the system.