The roof of the building is mainly tile roof and concrete roof. For the installation of domestic photovoltaic power plants, the following points should be noted in the preliminary site survey.
On-site survey requires preparation of tape measure of more than 20 meters, laser range finder (can be purchased online, the price is not expensive), compass or mobile phone compass APP and paper and pencil. If you need to tilt the roof, it is recommended to put on the safety rope on the non-slip laces.
First, the construction survey points
1. Ask about the year of completion of the building and the ownership of the property.
2. Roof orientation and azimuth. On-site compass measurement plus google satellite map query.
3, the roof tilt angle. The roof tilt angle can be calculated by measuring the width of the roof and the width of the house. The angle of the roof of the south is generally larger than that of the north roof, and the roof angle of the Shanghai area is about 30°.
4, tile type, tile size. Common tile types for civil buildings include Roman tiles, hollow tiles, double-slot tiles, asphalt shingles, flat tiles, fish scale tiles, Spanish tiles and slate tiles. If the tile size is not easily measured at the site, the size can also be queried online after determining the tile type. Because the size of the tile, especially the thickness, determines the selection of parts such as the solar mounting bracket system hook.
5. Consider the occlusion of the roof. Accurately measure the size of the obstructions around the roof, and later use the shadow analysis software to model the area map of the available roof. Shadow occlusion on the solar panel can greatly affect the amount of power generated.
6. Open some tiles to view the roof solar mounting structure, pay attention to the size and spacing of the main beams and beams. The bracket system solar hook of the tile roof is mounted and fixed on the stringer.
1. Year of construction completion, ownership of property; roof orientation and azimuth.
2. Measure the height of the parapet wall, and perform shadow analysis later to determine the area that can be installed and utilized.
3, to view the roof waterproofing, in order not to damage the roof waterproof solar panel mounting structure, consider whether the solar panel support bracket is installed from the (negative) heavy or expansion bolts. The load capacity of the standard civil concrete roof should be greater than 3.6KN/m2. The load of the support system is also less than the load capacity of the concrete roof considering the short-term wind load and snow load. In order to avoid any damage to the waterproof structure of the building after installing the photovoltaic system, the self (negative) heavy bracket installation method is preferred.
Second, electrical exploration points
1. Check if the incoming power is single-phase or three-phase. Civilian villas are generally three-phase power. The single-phase output photovoltaic power generation system should be connected to a phase where the three-phase dual-purpose incoming line switch uses more power. Conditions allow the use of three-phase inverters or three single-phase inverters.
2. Ask about the monthly average electricity consumption or electricity consumption and the main electricity consumption period. As a reference for the installation capacity of photovoltaic systems.
3. Check the capacity of the owner's incoming main switch. Considering the revenue problem, the output current of the photovoltaic power generation system should not be greater than the capacity of the household switch. Under the current subsidy policy, it is still the most self-sufficient and fully self-sufficient.
4. Consider the installation position of the inverter and the network cabinet with the principle of convenient transportation. Inverter and grid-connected cabinets are also installed in consideration of heat dissipation, ventilation and waterproofing.