Main content:
As the global demand for renewable energy continues to grow, the micro inverter combiner box as an important component of the solar power system, plays an important role in improving the efficiency of solar power generation, it not only improves the efficiency of solar power generation, but also provides a guarantee for the stable operation of the system. This articles discusses functions, working principles, purchasing points and application in solar photovoltaic system as well as maintenance methods of micro inverter combiner box.
What is a micro inverter combiner box?
The micro inverter combiner box is an electrical device used in solar photovoltaic systems, which is connected to multiple micro inverters, and then the AC output generated by multiple micro inverters is summarized, and finally the electric energy is transmitted to the grid or electrical equipment.
You can check micro inverter vs string inverter for more details.
Each micro-inverter is installed on a photovoltaic panel and is responsible for converting the direct current generated on the panel into alternating current. It typically includes components such as circuit breakers, lightning protection, data acquisition modules, and human-machine interfaces to improve system efficiency and provide safety features such as overcurrent protection.
Working principle of micro inverter combiner box
The micro inverter combiner box brings together the electricity from multiple solar panels, and inside the combo box, each solar panel connection is equipped with a fuse or circuit breaker to provide circuit protection against current overload or circuit abnormalities and prevent equipment damage. Some bus boxes also have the monitoring function to provide fault diagnosis and operation and maintenance suggestions after real-time monitoring of the system running status.
The micro inverter in micro inverter combiner box itself works by converting the direct current generated by the photovoltaic panel into alternating current in order to supply power to the home or commercial grid. It converts direct current into high-frequency alternating current required by electrical equipment through the on-off and off-off of power electronic switches, such as MOSFET or inverter IGBT power switches, and may be processed by filtering circuits to become stable sinusoidal alternating current.
How to choose a micro inverter combiner box?
Voltage and power range:
Be sure that the power of the micro inverter combiner box is greater than the output power of the inverter, if the power rating of the micro inverter combiner box is less than the output power of the inverter, otherwise it may lead to overload and overheating, damage or even fire. The power generated by the inverter exceeds the support range of the micro inverter combiner box, which will cause excessive heating of the internal components of the inverter and burn the fuse or circuit breaker.
During operation, overload will lead to a decrease in the efficiency of the internal components of the inverter or the micro inverter combiner box, increasing the power loss and resulting in a decrease in the overall power generation efficiency of the photovoltaic system. The terrible thing is that long-term overload operation will accelerate the wear of internal components, thereby shortening the life of the equipment. Operating at the right power and inverter voltage ratings helps the system to operate stably within the rated range, thereby extending the life of the bus and the entire photovoltaic system.
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Safety protection function:
Sometimes, there may be excessive current overload phenomenon, because choosing a micro inverter combiner box with overload protection, lightning protection and short circuit protection is crucial, which involves personal safety issues, be sure to pay attention to it. Choose a micro inverter combiner box with overload protection function, which can automatically power off in the case of too much current to avoid equipment damage.
The high voltage electrical energy generated by lightning strikes passes through the system circuit instantaneously, which may break down the electrical components or cause complete damage to the equipment. Especially in lightning-prone areas, the lightning protection function can effectively reduce the impact of lightning strikes on the micro inverter combiner box and its connected equipment, ensuring that the system is not damaged by high-voltage current. If your area is prone to lightning, choose a micro inverter combiner box with a lightning protection device to prevent electric shock damage.
Ensure that the micro inverter combiner box has a complete short circuit protection function to avoid system faults or security risks caused by circuit faults. In a normal circuit, because the current will encounter a certain resistance when it encounters a load, these load resistors limit the current in the circuit to a certain range of values, so that the current is kept within a safe range. However, when a short circuit occurs, there is almost no resistance, which can easily lead to a rapid increase in current and cause a fire.
Common application scenarios for micro inverter combiner box
Micro inverter combiner box are commonly used in small residential systems and can be installed on the roof of a home. It is also commonly used in commercial rooftop photovoltaic systems and building integrated photovoltaic (BIPV) projects. They are suitable for small and medium-sized power plant projects, especially those requiring modularity and high security.
They are suitable for scenarios where some panels are shielded, ensuring that each solar panel can work independently, effectively improving power generation efficiency. After ensuring that efficient supply can be met, excess power is sent to the grid.
Maintenance methods for micro inverter combiner box
Regularly check whether the terminal is firm: ensure that there is no loosening or corrosion. Check that the circuit breakers and fuses are working properly. Otherwise, the resistance of the wiring position will increase, affecting the working efficiency of the inverter.
Regular cleaning: Clean the inside and outside of the micro inverter combiner box to ensure that there is no dust or debris clogged. When cleaning internally and externally, be sure to turn off the power and pay attention to whether there is dust or other debris inside the micro inverter combiner box, especially near the vents and terminal blocks. You can use a dry brush or compressed air to clean the inside. The exterior of the micro inverter combiner box is also susceptible to dust, rain, or other external factors. By regularly cleaning the dust on the surface of the shell, the ventilation and heat dissipation of the device can be ensured to increase inverter lifespan.
Regularly monitor the running status of the micro inverter combiner box: you can use a multimeter to connect the probe to the corresponding terminal of the micro inverter combiner box, read the measurement results, read the voltage, current and output power and other parameters to ensure that the indicators are normal. It can simulate the special cases of the micro inverter combiner box, such as regular simulated fault test, to check whether the protection function of micro inverter combiner box is normal in the case of overload, short circuit and so on.
Conclusion
As an important part of the solar photovoltaic system, the performance of the micro inverter combiner box will directly affect the power generation efficiency and safety of the whole system. I hope this article can let you more in-depth understanding of the working principle of the micro inverter combiner box, purchase points and maintenance methods, users can make better use of this equipment, to achieve efficient conversion and utilization of solar energy.
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