What conditions do you need to meet in the UV preconditioning test?

author: Source

The UV preconditioning test is designed for the testing of solar photovoltaic modules. It is used to evaluate the UV resistance of materials such as polymers and protective layers. It can quickly and truly reproduce the damage of sunlight, rain and dew on materials: it only takes a few days or In a few weeks, it can reproduce the damage that can take months or years to come out: including fading, discoloration, brightness reduction, chalking, cracking, blurring, embrittlement, strength reduction and oxidation. Reliable aging test data can be The weathering (anti-aging) properties of the product make accurate correlation predictions and contribute to the screening and optimization of materials and formulations.

The main functions of the UV pretreatment test machine:

1. The UV preconditioning test machine uses the original UVA-340 fluorescent UV lamp imported from the United States as a light source to simulate the weathering resistance of the PV module by simulating the ultraviolet radiation in natural sunlight to obtain the weather resistance of the material.

2. The temperature and light irradiance can be automatically monitored; the radiometer can be configured to control and correct the irradiance, so that the irradiance is stabilized at the specified illuminance and the test time is controlled.

UV preconditioning test machine description:

     1. Horizontal design to ensure the effective stability of the light source;

     2, double door lock joint control, to ensure no UV light leakage;

     3, open interior design to ensure exchange with the outside air;

     4. Special guide rails to facilitate the push-in and pull-out of components;

     5, electric heating technology, using bang-bang control theory to accurately heat;

     6. The infrared temperature sensor accurately measures the surface temperature of the component, and the test accuracy is ±0.0.5 °C;

     7, voltage signal control ballast, amplitude modulation 5% 100% 5% ~ 100% 100%;

     8, imported sensors, built-in signal amplification system to reduce the impact of external interference signals

     9. Each group of sensors controls a group of ballasts to control two light sources;

     10, irradiance real-time monitoring of radiation intensity automatic compensation to ensure uniformity and accuracy;

     11, temperature (inverter air cooling) control, high control accuracy coefficient, temperature tolerance within ± 3 ° C;

     12. The ballast is equipped with a lamp start protection function to provide a lamp status alarm.


UV preconditioning test conditions:

    1. Test purposes

    Ultraviolet (UV) irradiation pretreatment is performed prior to the thermal cycling/wet freezing test of the assembly to determine the UV attenuation of the associated material and the adhesion joint.

    2. Test device

    a) Equipment capable of controlling the temperature of the module when subjected to UV irradiation. The temperature range of the module must be 60 °C ± 5 °C.

    b) A device for measuring the temperature of the recorded component with an accuracy of ±2 °C. The temperature sensor should be mounted on the front or rear surface near the middle of the assembly. If more than one component is being tested at the same time, only one representative component temperature should be monitored.

    c) An instrument capable of testing the ultraviolet irradiance on the test plane of the component, with wavelengths ranging from 280 nm to 320 nm and 320 nm to 385 nm with an accuracy of ±15%.

    d) ultraviolet radiation source with an irradiance uniformity of ±15% on the component test plane, no detectable radiation of less than 280 nm wavelength, capable of producing the required irradiance in the spectral range of interest according to item 3 below .

    3. Test procedure

    a) Measure the irradiance on the test plane of the component using a calibrated radiometer to ensure that the irradiance at wavelengths between 280 nm and 385 nm does not exceed

    250 W·m-2 (approximately equal to 5 times the natural light level), and the irradiance uniformity across the measurement plane reaches ±15%.

    b) Install the open-circuit assembly to the measuring plane selected at step a), perpendicular to the UV light. The temperature range of the component is guaranteed to be 60 °C ± 5 °C.

    c) subject the module to ultraviolet radiation having a wavelength in the range of 280 nm to 385 nm of 15 kWh·m-2, wherein 3%-10% is the amount of ultraviolet radiation in the range of 280 nm to 320 nm, and the temperature of the component is maintained during the test. The scope.

    4. Final test

    Repeat the test of visual inspection, maximum power determination and insulation test.

    5. Test requirements

    The following requirements should be met:

    (1) No serious appearance defects;

    For design identification and styling, the following defects are serious cosmetic defects:

      (a) breaking, cracking, or detachment of the outer surface, including the upper layer, the lower layer, the frame, and the junction box;

      (b) curved, irregular outer surfaces, including irregularities of the upper, lower, frame and junction boxes that affect the installation and/or operation of the components;

      (c) a crack in a battery whose extension may result in more than 10% of the area of ​​more than one battery being reduced from the circuit of the component;

      (d) forming a continuous bubble or delamination channel between the edge of the component and any portion of the circuit;

      (e) Loss of mechanical integrity, resulting in the installation and/or operation of the components being affected.

    (2) The attenuation of the maximum output power does not exceed 5% of the test value before the test; 5%;

    (3) The insulation resistance should meet the same requirements as the initial test.