In recent years, the technology of the photovoltaic industry has developed faster and faster, the power of a single module has become larger and larger, and the current of the string has become larger and larger, and the current of high-power modules has reached more than 17A. In terms of system design, the use of high-power components and reasonable over-provisioning can reduce the initial investment cost and kWh cost of the system.

DC cables are installed outdoors. It is generally recommended to select photovoltaic special cables that have been cross-linked by irradiation. After high-energy electron beam irradiation, the molecular structure of the insulating layer material of the cable changes from linear to three-dimensional network molecular structure, which is resistant to temperature. The grade is increased from non-cross-linked 70°C to 90°C, 105°C, 125°C, 135°C, and even 150°C, which is 15-50% higher than the current carrying capacity of cables of the same specification, and can withstand severe temperature changes and chemical erosion. Used outdoors for over 25 years. When selecting the DC cable, it is necessary to select products with relevant certifications from regular manufacturers to ensure the needs of long-term outdoor use.

The AC cable can be selected according to the maximum output current of the inverter. Because no matter how much the components are over-configured, the AC input current of the inverter will never exceed the maximum output current of the inverter.

The circuit of the photovoltaic system is divided into a DC part and an AC part. The two parts of the circuit need to be wired separately. The DC part is connected to the components, and the AC part is connected to the grid. There are many DC cables in medium and large power stations. In order to facilitate future maintenance, the wire number of each cable should be firmly attached. Separate strong and weak wires. If there are signal wires, such as 485 communication, they should be routed separately to avoid interference. When routing the cables, prepare conduits and bridges, and try not to expose the cables. It will look better when the cables are routed horizontally and vertically. Try not to have cable joints in the threading pipes and bridges, because maintenance is inconvenient. If aluminum wires are used instead of copper wires, reliable copper-aluminum transfer terminals must be used.