The main functions of the grid-connected distribution box include the following aspects:

Power Distribution and Access: The grid-connected distribution box is one of the core devices in a solar photovoltaic power generation system. Its main function is to connect the electricity generated by the photovoltaic power generation system to the power system, enabling self-consumption or surplus power to be fed back to the grid. It can effectively distribute the electricity generated by the photovoltaic power generation system into the grid, ensuring the stable operation of the power system.

Protection functions: The grid-connected distribution box is equipped with multiple protection measures, such as overcurrent protection, overvoltage protection, undervoltage protection, short-circuit protection, etc. These can effectively prevent the impact on the power grid caused by faults such as short circuits and overcurrents in the inverter, ensuring the safe operation of the photovoltaic power generation system. 

Electric energy storage and management: When the power grid can absorb the electricity generated by the current photovoltaic power generation system, the grid-connected distribution box directly feeds it into the power grid; when the power grid cannot absorb it, the electricity can be directed into energy storage devices for storage and used later. 

Anti-islanding effect: The grid-connected distribution box has the function of preventing the islanding effect. When the photovoltaic side experiences related conditions such as voltage, frequency, and overload, it can quickly cut off the faulty circuit to prevent any impact or influence on the power grid. 

Intelligent Grid Connection and Fault Handling: The grid connection distribution box is equipped with an intelligent grid connection function. It can trip the switch when the grid side or the photovoltaic power station side is abnormal, and automatically resume grid connection when everything returns to normal, without the need for manual operation. Meanwhile, it can also communicate through monitoring and remotely operate the opening and closing of the grid connection switch. 

Electricity metering function: Some grid-connected distribution boxes can be equipped with electricity meters and metering devices as per user requirements to record relevant information such as power generation and power consumption. 

Lightning protection: The grid-connected distribution box is equipped with a lightning arrester, which can effectively prevent damage from natural disasters such as lightning strikes and ensure the safe operation of the electrical system. 

These functions make grid-connected distribution boxes of great significance in solar photovoltaic power generation systems. They not only ensure the stability and safety of the power system but also optimize the efficiency of power usage, reduce electricity costs and minimize environmental pollution.