How Does a PV Combiner Box Work?

The PV combiner box is a complete set of devices to ensure the orderly connection and convergence of PV strings in the PV power generation system. Generally equipped with surge protectors, leakage protectors, isolation switches, fuses, etc., it provides isolation, leakage and grounding protection, ensures that the PV system is easy to cut off the circuit during maintenance and inspection, and reduces the scope of the blackout when the PV system fails to improve the performance of the PV system. So how does a PV convergence box work? Power Home will answer your questions in this blog!

DC PV combiner box is generally used in medium and large-scale photovoltaic power generation system, the user will be a certain number of the same specifications of the photovoltaic modules connected in series to form a photovoltaic array, and then a number of photovoltaic arrays in parallel access to the photovoltaic convergence box, the photovoltaic array of multi-output cables focused on the input, grouped together in a connection, not only to make the connecting line in order, but also to facilitate the group checking, maintenance, when the photovoltaic module array of localized failures When a local fault occurs in the PV module array, it can be partially detached for maintenance without affecting the connection of the overall power generation system.

AC PV combiner box is an important part to take over the output of string inverter and the input of AC distribution cabinet or step-up transformer, which can collect the AC power output from multiple inverters and then output, greatly simplifying the connection line between string inverter and AC distribution cabinet or step-up transformer. At the same time, the access of AC PV combiner box, as the output disconnection point of the inverter, can also protect the inverter from the hazards of the AC grid, improve the safety of the system, and protect the safety of the installation and maintenance personnel.

The working principle of PV DC converter box mainly includes the following steps.

1. Solar panel generates DC current: Solar panel generates DC current under sunlight irradiation, which is input to DC converter box through connector.
2. DC Current Concentration: DC current flows through the convergence strip to concentrate the output current of multiple PV panels into a single convergence strip.
3. DC Circuit Breaker Protection: DC circuit breaker monitors the magnitude of DC current and cuts off the circuit when the current exceeds the rated value to protect the safety of electrical components.
4. Electrical Connector Transmission: The centralized DC current is transmitted to the inverter through the electrical connector.
5. Lightning protection: The lightning protection device protects the PV system from lightning strikes and overvoltages by directing and dispersing the lightning current.
6. Temperature and humidity control: Temperature and humidity controllers monitor and control the temperature and humidity inside the convergence box to ensure the normal operation of the electrical components.

Through the above steps, the PV DC convergence box can effectively centralize and protect the DC output of the PV panels to provide reliable DC current to the inverter for further processing.

The working principle of the PV combiner box can be imaginatively understood as the "current collection station", and its main task is to unify the management and distribution of the power generated by the photovoltaic panels. It not only collects the current and voltage signals of each group of panels, but also converts these signals into standard signals and outputs them to the centralized controller. At the same time, it also provides independent protection for each group of panels, once found abnormalities such as over-voltage, over-current, reverse current, etc., it will immediately and automatically cut off the circuit to protect the panels from damage.

The function of the PV combiner box is more in favor of practical application. It can prevent the PV panels from localized failure and ensure the working stability of the whole system. Through the independent current and voltage signal acquisition function, the current and voltage of each group of panels can be adjusted and monitored in time to improve the power generation efficiency. Moreover, when the solar panels have overcurrent, overvoltage and other faults, the convergence box will cut off the shen circuit through fuses, switches and other devices in time to avoid damaging the solar panels and inverters and other equipment. In addition, the convergence box also provides a convenient way to maintain the PV panels. When you need to repair or replace the panel, you only need to disconnect the output of the convergence box, which greatly simplifies the operation process. The convergence box is also equipped with a variety of sensors to monitor the operating status of each solar panel and transmit the data to the centralized control system for timely detection and repair of faults.