1. Protection glass
- allows an excellent sunlight transmission in order to produce electricity;
- has a protective role for the photovoltaic modules (protection against external factors such as wind, frost, rain, snow, corrosion and accidental impact);
- very good mechanical performances 5400Pa;
- Kiwa certified.
2./4. EVA foil
- very good UV protection: 360mm;
- allows a high sunlight transmission;
- the high quality of the gel used in the EVA foil composition gives the perfect encapsulation;
- Kiwa certified.
3. Solar cells
- acquired from the world’s leading manufacturer in the field;
- have a long-term high efficiency, i.e. 18.2%;
- excellent performance under high temperature and low solar radiation conditions;
- 1% tolerance for each photovoltaic panel;
- fitted with an anti-reflective coating, providing 100% absorption of sunlight energy;
- the negative surface contact rods are made from aluminum and have a 1,4mm thickness;
- the positive surface contact rods are provided with aluminum and have a 2,5mm thickness.
5. Back foil
- UV tested;
- UL and Kiwa certified;
- composed of 3 layers, or 2 PA layers and 1 PET layer;
- excellent protection against weathering, insolubility and erosion;
- only available in the white version;
The back foil is characterized by long durability and endurance against damages and yellowing.
- made of pure aluminum;
- titanium anodizing;
- high corrosion endurance;
- allows a good paint adhesion;
- act as electrical and thermal insulator;
- excellent endurance to abrasion and scratches.
7. Junction box
- stable and secure connection;
- the external material of the housing is UV resistant and is designed to withstand weathering over extended periods of time;
- IP65 protection degree;
- specially designed for easy replacement of the diodes.
8. Solder alloy
- chemical composition: 63% Sn, 36% Pb and 2% Ag;
- dimensions: 1,7mm width and 0,2mm thickness;
- the soldering operation on the cell surface is executed only with Kaster 955, at the recommendation of the solar cell producer;
In the photovoltaic panels manufacture process we use high quality raw materials. These are subject to repeated and rigorous inspections. The innovative, cutting-edge technologies, along with the high quality raw material, ensure the long yield of the photovoltaic panels.
1. Solar cells preparation
The cells carefully placed in the specially designed supports, located inside a unit protected and provided with an opening sensor, are being picked up by a hydraulic arm provided with suction cups. Each cell is automatically centered, with a precision of 100%, on a device. Furthermore, the cells are picked up by the same hydraulic arm for manual positioning on the strings formation belt.
2. Protection glass preparation
Before being introduced in the production flux, the glass is cleaned with a special solution. The glass role in the context of the photovoltaic modules formation is to protect the solar cells by the direct contact with the atmospheric agents and to grant rigidity to the manufactured module. Simultaneously, the EVA foil is prepared to be introduced in the technological flow. The EVA foil is cut to the correct dimensions: 1657mm x 998mm for the photovoltaic panels containing 60 solar cells or 1958mm x 998mm for those containing 72 solar cells. With a maximum caution, the EVA foil will be placed above the protection glass. The created ensemble will be subject to the strings soldering operation (stage 3).
3. Cell strings formation
The use of a professional stringer machine eliminates the risk of human errors occurrence. The cell strings formation with a certain polarity is executed by a complex soft soldering mechanism on the cells surface. The formed strings reach the protection glass with the help of the conveyor belt. Furthermore, the formed cell strings are picked up by the hydraulic arm and placed, with precision and accuracy, on the previously formed ensemble.
The main advantage of using the fully automated system is the execution of the quality control during the entire technological flow.
The high quality of the operations is guaranteed by the automatic execution of the work operations in a synchronized manner, in a dust protected environment. The use, in the manufacturing process, of automatic machines capable of performing complex operations with a maximum precision, as well as the operator’s training, qualification and specialization, significantly contribute to confirming the superior quality of the photovoltaic modules.
4. Conductors soldering
The cell strings are manually connected in series by the operators. This operation of connecting in series is carried out by personnel with high attention to details and exquisite practical skills. Simultaneously, automatically, the connections are carried out according to the current input-output characteristics.
The interconnection ribbon to which the solder wire ends are connected is placed as a reel. This is debited to the programmed dimension. Thus, the operation is automatically executed, with a maximum precision, safely and with a minimum human effort.
5. Picotest testing
The above formed assembly is verified with the Picotest test. The testing is possible due to the previous stage electrical pre-charge. The test consists of measuring the electrical parameters with the professional measuring device. Subsequently, on the visual inspection table, the solar cells positioning is verified. If the resulting ensemble meets all the necessary characteristics in order to obtain the high quality of the final product, the EVA foil and the back protective foil will be attached to it. Otherwise, the manufactured ensemble is not used as a component element of the photovoltaic module.
The testing of the ensembles formed during the entire technological flow, allows the quality control of the entire flow. The products’ quality control is, for our clients, the main guarantee of the purchased products’ high quality.
6. Photovoltaic panels lamination
The lamination is executed by the complex lamination system, achieving the perfect vacuuming of the previously formed ensemble. The accurate setting of the work sequences determines the perfect adherence of the component layers. The laminator works in vacuum at a fixed temperature, respectively 156°C, preventing this way the occurrence of possible errors. The temperature application has the role to modify the EVA foil proprieties. After lamination, from the polymer plasticized EVA foil, a plastic material layer is obtained that will not melt and where the solar cells are encapsulated and tightly soldered to the protection glass and the foil.
The work precision is the main advantage in using the laminator. Being an automated technological stage, the human factor involvement is minimum, determining the reduction of the errors’ occurrence risk.
After the cooling, the photovoltaic panel is visually inspected. The testing, or the visual inspection, purpose is to obtain high quality and high efficiency photovoltaic modules.
7. Photovoltaic panels framing
On the finishing table, provided in the central area with a mobile disc, the panel is rotated for cutting the waste heads in order to adjust the extra margins after lamination. At the same time, the frames are prepared to be introduced in the production process. The framing is done by the specialized application equipment. The frames lining is done automatically by an advanced system. The corners are blocked in fixed position into the frames with a special machine. The silicon is being applied automatically with another advanced equipment.
The hard aluminum profiles fulfill a dual role, namely to insure the photovoltaic module rigidity and the easily fixing of the modules to one another or on a bracket.
8. Junction box application
The junction box provided with bypass diodes is manually mounted by an operator. The bypass diodes are connected in parallel with the output terminals of each panel. The diodes fulfill a dual role: to limit the solar cells’ warming and to maintain constant the current’s intensity if the circuit is less efficient or shaded.
The insulating cables and wires are designed to minimize the voltage and the power losses.
9. Photovoltaic modules’ characteristics testing
The manufactured photovoltaic module is tested with a cutting-edge complex system that simulates the actual conditions of one day in only 5 seconds. The light testing of the photovoltaic module consists in executing the current-voltage testing. The high accuracy of the current and voltage characteristics measurement is determined by the light source uniformity, whose radiation parameters remain constant throughout the testing.
The photovoltaic modules’ characteristics are measured only in the presence of the quality responsible personnel. The measured characteristics are:
- open circuit voltage Voc
- short circuit current ISC
- optimum voltage UMPP
- maximum current IMPP
- maximum power PMPP
- fill factor FF
- power change coefficient with the cell temperature
- solar cell efficiency ɳ.
The testing results are recorded, irrevocably, in the memory of a computer and can be read automatically via the installed special software.
A sticker is automatically generated, printed with the results generated from testing. The sticker confirms the performance of each manufactured photovoltaic module, being easily read and understood by everyone.
The photovoltaic module is continuously tested throughout the technological flow, ensuring this way the quality control of the entire technological flow.
10. Electroluminescence testing
The electroluminescence testing is the testing executed in each solar cell of the manufactured photovoltaic modules.The test helps verify if the encapsulated cells showed damages during the production process. The test result is presented as a diagram. The generated diagrams are made available to the clients. Each diagram is saved in the database by the unique barcode on the front.
11.Corners application and Photovoltaic panels packing
The operation of corners application, made of a special material, is executed by an advanced, efficient and application specialized system. The importance of corners application is determined by the photovoltaic panels’ stacking.
The stacking is a vital operation in the storage and transport of the photovoltaic panels in maximum security conditions.
The packaging is automatically carried out using a complex packaging specialized system. The photovoltaic panels are packaged in sets of 26 pieces per pallet. Subsequently, the pallet is packed in foil and cardboard boxes (in sets of 25 pieces per box).
The packaging importance is essential and emerges from the main role of any package, namely to protect the photovoltaic panels from the occurrence of possible damages.