The plan is specially designed UV ageing proof box by BV company for the photovoltaic industry. Refer to IEC 61215-2005、IEC 61345-1998《UV test PV modules》national standards , design notes are as follows :

 

 

PV materials including silicon、polysilicon、amorphous silicon、GaAs、GaAlAs、InP、CdS、CdTe etc. Silicon、GaAs、InP are used for the space. Silicon、polysilicon、amorphous silicon mass production are used for ground.

EVA  is the capsule sealed  material of Crystalline silicon solar cells, which is ethylenevinyl acetate copolymer resin, chemical structure is as follows :

（CH2—CH2）—（CH—CH2）
        |
       O
        |
        C — O — CH2

The EVA after curing could withstand atmospheric changesbe flexible, which could encapsulate silicon chip group. With together the Protection of the upper glass materials,the protection of  bottom material TPT Poly  fluoride composite membrane, the EVA was components used in the back, the  back of protection as packaging materials, the use of vacuum laminating adhesive technology for integration.

 

There were two main EVA: ① the fast curing  ② the conventional curing . EVA different had different laminating process. Used anti-UV agents, antioxidantscuring agent for the thickness of 0.4 mm EVA film solar cell as a sealant, to meet with the glass, TPT adhesion between the close. Packaging for silicon solar cell components EVA, primarily on the basis of its own transmission of lightweather resistance properties to choose.

 

In the use of polymer materials often appeared in the process of the powder, discoloration, foaming, crack, shedding phenomenon, which has seriously affected the appearance of products,other aspects of performance.

Therefore, the need to understand the polymer materials-aging mechanismthe search for a suitable artificial accelerated aging test-objective approach to simulate natural conditions, so as to the developmentapplication of materials to provide rapid detectionevaluation of the quality of the basis.

Currently used artificial accelerated aging test method main xenon lamp, ultraviolet fluorescent lamps, metal lamps,carbon arc lights etc.. The backplane materials composite membrane general we seek to reduce heat absorption,effectively prevent excessive battery temperature increase reduces component / battery conversion rate, but xenon light source 280 to 3000 nm in the infrared spectrum easily lead to the absorption of heat components, the components used UV weatherable performance test.

The B.R. company developed BR-PV-UV PV modules UV-testing machine dedicated to the PV modules resistant to climate experiment.

 

Below would describe the aging of materials photovoltaic componentsthe major mechanism of accelerated aging test methods, thereby providing materials to the developmenttesting of personnel as a reference.

 

 

Polymer materials in the solar irradiation, would be a series of reactions, mainly photochemical reaction. According to photochemical reaction first, second law of a photochemical reaction material might first absorb sunlight, that was, material atoms or molecules could absorb light energy, high-energy molecules or atoms in the state; This was followed by a molecular or atomic absorption of energy must be greater than bond energy, in order to make a material degradation, namely, aging. And polymer materials often contained residues in the process of polymerization of trace impurities catalyst residues or oxidation products, the polymer itself contained a number of irregular structure of the aging of their chemical structure weaknesses.These polymeric materials in the solar irradiation, the material weaknesses in the aging of the first to be captured in atoms or molecules bond cut,crosslinking, chain movement,the side chain fracture phenomena such as changes in the individual or simultaneously. Aging was complete depolymerization reaction to the end of polymer from the weak bonding between atoms of the fracture. After aging the polymer materials which appeared powder, discoloration, foaming, crack, shedding phenomenon. Polymer wavelength sensitivity of the impact of the aging was an important factor, the common wavelength sensitive materials shown in the table below:

 

UV fluorescence light was the low-pressure mercury lamp with wavelength on 254 nm, since entry into the coexistence of phosphorus into the longer wavelength. The energy distribution of UV fluorescent light depended on the emission spectra of phosphorus coexistencethe glass tube-expansion. UV fluorescent light was the same as the  domesticcommercial light,  with a specific spectral.

At present, there were two types of fluorescent lamps, fluorescent UVA UVA-351UVA-340fluorescent UVB F40UVB-313. Fluorescent comparison with the natural photoelectron spectra shown below:

 

UVA-340 comparison Sunlight            UVB-313 comparison Sunlight

 

As can be seen from Figure, fluorescent X-ray wavelength UVA mainly concentrated in the 340 to 370 nm, such as UVA-340UVA-351, UVA-340 short-wave radiation was very similar to the direct sunlight on 325 nm below  , the short-wave spectral distribution of UVA-351 was very similar to  sunlight through the windows. In the peak wavelength of fluorescent UVB F40UVB-313was  about 313 nm, the energy is concentrated almost entirely in between 280 ~ 360 nm, the wavelength of the energy distribution was shorter than sunlight，little energy in 360 nm or more. Such UVB lamps when it was used accelerating aging experiments, the data would often be different from naturaloutdoor in testing the stability of materials. This was because the short-wave ultraviolet light source such a large percentage of energy,the lack of long-wave ultravioletvisible part of the energy, therefore, this material might be related to the aging of the "natural" test a big difference.  .

 

 

 

To precondition the module with ultra-violet UV radiation before the thermal cycle/humidity freeze tests to identify those materialsadhesive bonds that are susceptible to UV degradation.

 

a   Equipment to control the temperature of the module while it is irradiated by UV light. The equipment must be capable of maintaining the module temperature at 60℃ ±5℃.

b  Means for measuringrecording the temperature of the modules to an accuracy of  while it is irradiated by UV light ±2℃.Te temperature sensors shall be attached to the front or back surface of   the module near the middle. If more than one module is tested simultaneously, it will suffice to monitor the temperature of one representative sample.

c  Instrumentation capable of producing of measuring the irradiation of the UV  light produced by the UV light source at the test plane of the modules,within the wavelength ranges of 280 nm to 320 nm320 nm to 385 nm with an uncertainly of ±15%

d  A UV light source capable of producing UV irradiation with an irradiance uniformity of ±15% over the test plane of the modules,with no appreciable in the different spectral regions of interest as defined in 10.10.3

 

a Using the calibrated radiometer measure the irradiance at the proposed module test planeassure that at wavelengths between 280 nm385 nm it has a uniformity of ±15% over the test plane

b Mount an open-circuited module in the test plane at the location selected in a, normal to the UV irradiance beam. Make sure that the module temperature is ±5℃.

c Subject the modules to a total UV irradiation of 15kwh.m^-2 in the wavelength range between 280 nm385 nm, with at least 5 kwh.m^-2  in the wavelength band between280 nm320 nm, while maintaining the module temperature within the prescribed range.

 

Repeat the test of 10.1, 10.210.3

 

The requirements are as follows:

No evidence of major visual defects, as defined in clause 7;

The degradation of maximum output power shall not exceed 5% of the value measured before the test Insulation resistance shall meet the same requirements as for the initial measurements.

 

 

 

Reference IEC 61215-2005, IEC 61345-1998,GB / T 19394-2003 "photovoltaic PV components UV test" corresponding standard clauses, which  instrument was designedmanufactured,technology indicators in the programme book for this technology.

 

1. Specifications

Effective radiation region: 2000×1000mm W×D

Centre distance of lamps: asymmetric arrange

Radiation intensity: Automatic adjustments to ensure that ± 15%

Uniformity of the test plane irradiation

Temperature Resolution: 0.01 ℃

Test temperature: 60 ℃ ± 5 ℃

Control: Control + touch screen PLC programmable logic controller

or PC computers Control

Instrument proposed use of the environment: 5~35 ℃, low humidity, the distance about 300 mm from wall.

 

2. Main function

BR-UV-PV-testing machine used UV ageing UVAUVB-340 UV-313 fluorescent lamp as light source, by simulating natural sunlight in the ultraviolet radiation, accelerated weathering photovoltaic components of the test in order to obtain material Weathering of the results.

 

BR-UV-PV can be temperature, light irradiation for automatic monitoring; configuration of radiation, the radiation controlcalibration, radiation stability in the designated illumination, at the same time control of the trial time.

 

3. Introduction of sub-item

Centre distance of light was arrange, reference to the recommended conditions from foreign counterparts,B.R. conditions to ensure uniformity of the radiation.

 

The light source was came from the 40 W rated power of the United States original import UVA-340UVB-313 UV fluorescent, a total of 28 UV fluorescent tubes installed in the top of the apparatus.

 

In accordance with the requirements of IEC standards, UVA-340UVB-313 must combine to use ，as one UVA-340one UVB-313, respectively radiation monitoring, to satisfy the 280nm~320nm within 7.5 KW • H/m² 5KW • H/m²320nm~400385 nm within 15 KW • H/m² the two bands on the radiation requirements.

 

As Fluorescent energy output would gradually decay over time, in order to reduce the energy for light attenuation caused by the impact of the trial,the requests of IEC 61215 & IEC 61345 No.5-a uniformity of the radiation ± 15 per cent. The Chambers designed lamp current control system,thus gained a constant optical output power.

 

Under normal circumstances an effective lamp life was about 1600~1800 hours. Since the BR equipment installed radiation control system, the attenuation of light could thus increase the current compensation for irradiance, it would extend the life of lamp to about 2500~5000 hours.

 

3.2. Electrical Control

a、Use HMI+PLC, can be programmed automatic control of temperature, radiation, exposuretest time.

 

Irradiance, temperature, time of test conditions or results  as well as working curves could  be storedprinted.

 

Man-machine dialogue, the high degree of automation,the full realization of the automatic monitoring of radiation.

 

According to user requirements, PC control, external PC computers, Windows XP user interface,the realization of data or curves of the work storageprinting function.

 

Unlimited time control, with a total timepower outage memory function.

 

After the test was completed, the test indicator which was installed in the control panel surface would issue remind signal, at the same time the test would be terminated.

 

Irradiance uniformity: ± 15% in the sample surface

 

Temperature Monitoring: BR-PV-UV used the Pt-100 standard temperature sensors, precision control in the process of testing the ambient temperature, or temperature of the sample surface.

 

Blackboard temperature sensor was consumables, if use blackboard thermometer, it should be regularly cleaned, the surface paint might be falling after a certain period of time, the accuracy of control would be affected. If found marked changes in color, need to be replaced,the specific time by the use of decision, generally for about  two years.

 

b、Special ballast, 5%~100% for adjustable to ensure that energy attenuation of the light energy of automatic compensation.

 

c、Security protection devices

Configurated overtemperature protection device ,installed alarm indicator in control panel. When the pilot compartment temperature exceeded a set limit, alarm sound machines would automatically cut off the lampheater power supply,access to a state of equilibrium cooling.

 

Protection locks optional:  If the lamp in the open state, cabinet doors were opened, the machine would automatically cut off the lamp power supply,automatically enter a state of equilibrium cooling, in order to avoid hurting the human body. Safety locks was in line with the IEC 047-5-1 security requirements. Strengthening locks sealing, the leakage rate can be less than when the daily sunlight penetrating the window 10% of UV intensity.

 

d、Irradianceradiation dose:

Component minimum acceptable radiation levels: ① IEC 61345-1998 ultraviolet light source wavelength at 280nm~320nm within the scope of 7.5 KW • h/m² ② IEC 61215-2005 ultraviolet light source wavelength at 280 nm ~ 320nm within the scope of 5 KW • h / m² ③ IEC 61345-1998 ultraviolet light source in the 320 nm ~ 400nm within the scope of 15 KW • H/m², ④ IEC 61215-2005 ultraviolet light source at 280 nm ~ 385nm within the scope of 15 KW • H/m²,to ensure that no radiation below 280 nm degrees.

 

Implementation of IEC 61345, respectively set up 280 ~ 320 nm radiation is 7.5 KW • h/m²320 ~ 400 nm radiation in the 15 KW • h/m²; implementation of IEC 61215, respectively, set up 280 ~ 320 nm irradiation of 5 KW • h / m²320 ~ 385 nm radiation in the 15 KW • h/m². Finished input parameters, apparatus, automatic completion of the pilot.

 

①On-line use of the standard long-wave optical sensor, by 280~320 nm、320~400nm at stalls. Radiation exposure from the industrial LCD displaycontrol.

 

②If IEC 61345-1998 implementation of standards, the use of on-line, long-wave standard photoelectric sensor, by 280~320 nm, 320~400nm at stalls.

 

③Resettlement outside the sensor calibration, choose to use from the United States company, with the number of sensors can be replaced UVblue light irradiation intensity.                                                                                                                                        

Factory calibration, propose a test every year.

Measurement range: Long wave 320~400nm

Measurement range: Medium wave 280~320nm

Measurement range: shortwave 230~280nm

Rarely used, generally not recommended

Range: 0~19,990µW/cm² 199.9W/m²

Resolution: 10µW/cm²

Show: 4½, 7 LED display, 0.4 inch10mm hight

Conversion rate: 3 readings per second.

Host Size: 7¼L×3½W×2"D 18.4L×8.9W×5.1cmD

Weight: 3/4 lb 0.75kg

Sensor Size: 3L×2W×½"D 7.6×5.1×1.3cmD

Weight: 1¼ oz 35.4g

Sensor cable length: 4 ft 121.9cm

Necessary power: a 9 V alkaline batteries

 

DIX-Series sensor main parameters are as follows:

□ All sensor temperature coefficient: ±0.025%/℃ 0~50℃

□ sensor measurement wavelength range: Medium wave 280~320nm

□ sensor measurement wavelength range: Long wave 320~400nm

 

Irradiation of the major advantages:

□ Widerbetter definition of interference band-pass filter to eliminate infraredother unwanted wave impact.

□ Solid silicon photosensitive diode was sealedfixed in waterproof metal / quartz packaging, to prevent vibrationhumidity affecting the accuracy.

□ Sensor shell was made by a series of shadesparticularly automatic sealed machinery, to remove UV-light leak.

□ Full accuracy of better than ± 5% can be directly traceable to NIST standards.

□ Demarcated by Pyroelectricity intensitometer ,to ensure that the most accurate.

All models automatically cleared, with excellent linearitycosine response, solid design, durable, easy to operate, with low battery power indicator light.

 

Sensor Lambertian reaction

In the UV-light irradiation different perspective, the sensorscosine curve of SP company were fitting intact.

 

Intensitometer spectral response

 

 

If implement IEC 61215-2005 standards, BR autonomously developed filter, wavelength range 320~385nm, fully meet the standard requirements, scanner map as follows:

UV Radiation Control: BR autonomously developed Radiation Monitoring System,regulated electric current of UV lamp, to meet the radiation of different wavelengths in test.

 

e、Unique exhaust system in proof box, avoiding the ozone from UV radiating, was requirement from the standard recommended.

 

f、Two irradiance probes with different wavelength range were fitted on transmission shaft, accurately fixed position in the center of every two lamps online, full scanning, automatic compensation of irradiation to ensure uniformityaccuracy.

Transmission belt containing steel materials, ensure that no deformation of high-temperature environments.

 

Transmission shaft was the internal, after measurement automatically contraction, timing detection, avoid the sensor prolonged exposure in their own aging environment to their own aging.

 

g、Proof box equipped with lights, cameras would be installed on the transmission shaft, without opening the container, it could be monitored the internal operation in time.

 

System choose ViewX or Simens series touch screen + Programmable Controller , maximum extent possible increase the system''s accuracyreliability,at the same time made the work of operators more simpleintuitive.

 

Programmable Controller let down the bars with only tunable humiture in the system,made UV irradiation degree easy to be tunable.

 

System scalability would be greatly improved, the programmers could amend interfaceprogram at any time based on user ’s needs ,extend the development space of the instrument, prolong the development life span.

 

System gather many technique light spots, such as to controling、automatic aiming 、servodriving、UV irradiation tracking the whole panorama、test database systemprint function.

 

System in strict accordance with the IECGB standards developmentproduction.

 

 

Photoelectric sensorcamera would be installed on the transmission shaft,  programme control , scan along the X-Y axis updown , auto-compensation irradiance baseline drift.

 

The proof box interior are used SUS304# stainless steel plate.

The proof box shell plate using electrostatic spraying.

 

Interior size: about W2200mm×D1100mm special custom specifications

Weight: about 700 kg

 

Power requirements: 220V±5%，single-phase three wire transformer, 50Hz，10A  slow-acting fuse.

 

A suit of UV radiation intensity measuring apparatus external proofread

A body of UVAUVB lighting tubes spare expendable

 

Two-year guarantee,not include UV irradiance meter、UV fluorescence lamp Maintain back-up components with 8 years stock.

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