Electroluminescence is a diagnostic process in which a camera capable of detecting near-infrared light is used to take image of a module. This procedure reveals a wide range of module defects, from casting the ingots to damage caused during transport. Electroluminescence is used for quality assurance during the manufacturing of the modules to find micro-cracks. These tiny cracks in the cells can lead to electrical insulation across entire segments of the panel. EL measurements are useful when conducting incoming goods inspections at the building site. Damages in the form of micro-cracks arising from transportation and rough installation processes are among the greatest risks for PV.
Power at STC (Standard Test Conditions)
Panel manufacturer claims maximum power output at photovoltaic module. Power loss from PID effect must be standard testing conditions (STC) . This number is a minimum and a power loss of 5% should not be exceeded baseline for design of all solar farms. PV Lab operates a Class AAA sun simulator for conducting all its power tests. in measurements before and after this period. Solar simulators are classified in accordance with IEC Peel-off test 60904-9. Low level of uncertainty are only possible when Class AAA simulator is used. This test is crucial to draw solid conclusion and serves to validate modules performance as claimed by the manufacturer
Power at low irradiance
Power at low irradiance is defined to be the output at an insolation of 200 W/m2. This figures can serve as a reference point for a high-quality module and are consulted when comparing modules in order to make the transparent bedding material can be released using a investment decisions. Power yields at low irradiance also form the basis for decisions by banks to provide financing for a system.
The test measures insulation resistance between the inner circuit and a water bath module is placed during testing. This test is relevant from a safety viewpoint.
Hot Spot Test (HS)
A thermographic camera is used to capture thermal images of a module. These images can reveal defects at soldering points, inactive regions in cells and formation of Hot Spots due to defective bypass diodes which can lead to irreversible damage to the module.
Potential Induced Degradation (PID)
Potential induced degradation, or the voltage dependent ageing of photovoltaic modules, is a type of power degradation that generally appears on the negative side of the module string and can affect almost any type of photovoltaic module. Power loss from PID effect must be minimum and a power loss of 5% should not be exceeded in measurements before and after this period.
This test aims to measure the adhesion of the bedding material (generally EVA) to glass. The peel-off test is valuable, because a peel-off force that is too low can indicate either that the production process was carried out with non-optimal parameters, or that materials past their expiry date have been used.
The EVA cross-linking test determines what percentage of the transparent bedding material can be released using a solvent. The remaining portion is then termed the cross-linking level. If the level of cross-linking is too low, it can be an indicator of an increased risk of delamination, which can ultimately lead to failure of the module.