Solar energy has revolutionized the way we produce and consume power, and as the industry grows, the need for efficient solar installations becomes more critical.
A combiner box is an essential component in a solar energy system, consolidating the output of multiple solar panels into a single electrical circuit. It simplifies the wiring process, reduces installation time, and makes maintenance more manageable. Link solar inverters and solar PV arrays, combining the output of a large number of strings to improve PV performance.

Solar Combiner Box: Expert Manufacturing of 1 to 36 String Configurations


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Combiner boxes provide essential protection against electrical faults, preventing fires and other hazards. High-quality combiner boxes have reliable overcurrent protection devices and robust surge protection mechanisms to safeguard your solar installation.


Efficient combiner boxes minimize power loss and ensure optimal energy transfer from the solar panels to the inverter. A well-designed combiner box ensures seamless electrical connections and reduces resistance within the circuitry.


A durable combiner box is critical for long-term solar installations. High-quality combiner boxes are built with corrosion-resistant materials, ensuring they can withstand harsh weather conditions and maintain their performance over time.


An experienced manufacturer with a proven track record in the solar industry is more likely to produce reliable and high-quality combiner boxes. Look for manufacturers with a history of successful installations and satisfied customers.


Certifications from recognized industry bodies and standards organizations indicate that a manufacturer's products meet or exceed specific quality and safety benchmarks. Look for combiner boxes that are certified by organizations such as ul, iec, or tüv to ensure that they comply with industry standards.


Every solar installation is unique, and your combiner box should be tailored to fit your specific needs. A reputable manufacturer should be able to customize their combiner boxes to accommodate varying numbers of solar panels, input and output connections, and monitoring requirements.



MOREDAY combiner boxes are equipped with higher-quality shells than those in the same industry to better protect internal components and provide long life. The MOREDAY combiner box can be installed outdoors. We add flame retardants to the casing, which can resist ultraviolet rays, be dustproof, anti-corrosive, and waterproof up to IP65 outdoors.

Our solar combiner boxes can provide effective protection for solar roofs anywhere, and our combiner boxes use top-brand DC circuit breakers, surge protectors, and fuse holders.

Temperature Range for PLASTIC PV DC Combiner Box MDJB-A / MDJB-B


In order to meet the needs of different customers, we provide many customization functions, including brand customization, component customization, system customization, and packaging customization.
We are willing to establish a long-term cooperative relationship with you. We have dedicated engineers to connect with you and provide you with full service. We are keen to bring comprehensive protection to your customers’ solar energy systems. This was also the original intention of MOREDAY.

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MDHL-2-1 3Phase
MDHL-2-1 3Phase
MDHL-3-1 3Phase
MDHL-3-1 3Phase
MDHL-5-1 3Phase
MDHL-5-1 3Phase
MDHL-6-1 3Phase
MDHL-6-1 3Phase
MDJB 1-1 63A 600VDC
MDJB 1-1 600VDC
MDJB 2-1 63A 600VDC
MDJB 2-1 600VDC
MDJB 2-2 63A 1000VDC
MDJB 2-2 1000VDC
MDJB 2-2 63A 1000VDC
MDJB 2-2 1000VDC
MDJB 2-2 63A 600VDC
MDJB 2-2 600VDC
MDJB 2-1 63A 1000VDC
MDJB 2-1 1000VDC
MDJB 3-1 63A 1000VDC
MDJB 3-1 1000VDC
MDJB 6-1 63A 600VDC
MDJB 6-1 600VDC
MDJB 4-1 63A 600VDC
MDJB 4-1 600VDC
MDJB 6-2 63A 1000VDC
MDJB 6-2 1000VDC
MDJB 4-1 63A 1000VDC
MDJB 4-1 1000VDC
MDJB 6-3 63A 600VDC
MDJB 6-3 600VDC
MDJB 4-2 63A 1000VDC
MDJB 4-2 1000VDC
MDJB-2-1 1000VDC
MDJB 4-2 63A 1000VDC
MDJB 4-2 1000VDC
MDJB 5-1 63A 1000VDC
MDJB 5-1 1000VDC
MDJB-4B 63A 600VDC
MDJB-5B 63A 1000VDC
MDJB-6B 63A 600VDC (With Diode)
MDJB-6B 600VDC (With Diode)
MDJB-6B 63A 600VDC
MDXLD PV3-1 63A 600VDC
MDXLD PV3-1 63A 1000VDC
MDXLD-PV2-1 63A 600VDC
MDXLD-PV2-1 63A 1000VDC
MDXLD-PV4-1 63A 600VDC
MDXLD-PV4-1 63A 1000VDC
MDXLD-PV4-1 125A 1000VDC
MDXLD-PV4-4 63A 1000VDC
MDXLD-PV5-1 63A 1000VDC
MDXLD-PV6-1 125A 1000VDC
MDXLD-PV8-1 125A 1000VDC
MDXLD-PV8-8 63A 1000VDC
MDXLD-PV18-18 63A 1000VDC
MDXLD-PV18-18 1000VDC
MDXLD-PV6-1 125A 1000VDC
MDXLD-PV10-1 1000VDC
MDXLD-PV10-10 63A 1000VDC
MDXLD-PV10-10 1000VDC
MDXLD-PV12-1 250A 1000VDC
MDXLD-PV12-1 1000VDC
MDXLD-PV12-12 63A 1000VDC
MDXLD-PV12-12 1000VDC
MDXLD-PV16-1 250A 1000VDC
MDXLD-PV16-1 1000VDC


A solar combiner box is an electrical box that houses several dc components. Moreday provides professional customized services to meet customers’ needs. We provide circuit customization for access to general inverter requirements, including your brand, box size, dc accessories, circuit input and output requirements, and mc4 connectors, etc. For customization, please send your requirements to our engineers.

Common Queries

Frequently Asked Questions

You'll find answers about our products. If your question is not answered below,
please feel free to contact us.
The main function of a combiner box in a solar system is to combine the current of multiple solar panels into a single output, which can effectively simplify the circuit wiring of the system.
Through the combiner box, not only can the wiring complexity be reduced, but it can also help optimize the management and distribution of current, thereby improving the power transmission efficiency and stability of the entire system.
In addition, the solar combiner box also has a protective function, which can protect the system from environmental factors such as dust, moisture, and overheating.
It is usually equipped with lightning arresters and short-circuit protection devices to ensure that the system can operate safely and stably in various climatic conditions. In this way, the combiner box not only improves the efficiency of the solar system but also extends the service life of the entire system.
The design of the solar combiner box is sophisticated and versatile. The main components include the following key parts:
Input connections: These are the interfaces connected to the solar panels and are responsible for receiving direct current from the panels. Each input connection is equipped with an anti-reverse diode to prevent reverse current flow and ensure that power can only flow in one direction.
Output connection: This is the part that connects to the inverter, which converts direct current into alternating current that can be used in homes or industries. The output connection ensures the smooth delivery of power to the inverter, which can protect the efficiency and safety of the entire system.
Overcurrent protection devices: Including circuit breakers and fuses, these devices are used to protect the circuit from excessive current. When an abnormal current is detected, these devices automatically cut off the circuit to prevent damage to electrical equipment or fire.
Surge protection devices: These devices are used to protect the system from sudden voltage increases, such as voltage surges caused by lightning. They can effectively absorb or disperse excessive voltage to ensure the long-term stable operation of the system.
Monitoring system: Modern combiner boxes are usually equipped with monitoring systems that can monitor the status of current and voltage in real-time, and some can even be remotely controlled and diagnosed. This makes system operation and maintenance more efficient and also facilitates the timely detection and resolution of problems.
Through the collaborative work of these components, the solar combiner box can effectively manage and protect the solar power generation system, ensuring power generation efficiency and system safety.

Investing in a high-quality Solar PV combiner box can provide reliable protection against electrical faults, effectively reduce power losses, and operate stably under harsh climate conditions. This combiner box prevents electrical faults through advanced protection devices, optimizes electrical connections to improve energy efficiency, and uses durable materials to resist environmental corrosion, ensuring long-term safe and efficient operation of the system.

In addition, high-standard Solar PV combiner boxes can significantly reduce operating costs and improve return on investment due to their durability and low maintenance requirements. They not only extend the service life of the solar energy system but also bring users higher economic benefits and better user experience.

When choosing a Solar PV combiner box manufacturer, you should consider the manufacturer’s industry experience, customization capabilities, product certifications, and warranty services provided. Choosing an experienced distribution box manufacturer can ensure product quality and technical support, while customization options and certifications ensure that the product can meet specific needs and safety standards.
The photovoltaic combiner boxes produced by Moreday have passed the stringent industry-standard certifications, including internationally recognized certifications such as CE, IEC, and TÜV.
These certifications demonstrate the superiority of its products in terms of safety, quality, and performance, ensuring that each combiner box can provide stable and efficient performance under various environmental conditions.
For customers seeking high-standard and reliable solar energy solutions, Moreday’s combiner boxes are a trustworthy choice that can meet strict international and regional technical requirements.
Yes, Moreday’s combiner boxes can be installed outdoors and have excellent weather resistance. Its shell is specially treated, flame retardant is added, and it can resist strong external radiation, while also having dust and corrosion resistance.

In addition, these combiner boxes have a waterproof rating of IP65, which can withstand harsh outdoor environments and ensure the safety and functional integrity of circuit components under various climatic conditions. Whether it is scorching sun, heavy rain, or other severe weather, Moreday’s combiner boxes can provide stable and reliable performance and are your ideal outdoor solar system configuration option.

When choosing a combiner box, special attention should be paid to the durability and adaptability of its materials to ensure long-term reliability in harsh environments. High-quality combiner boxes are usually made of high-grade plastics such as polycarbonate or specially treated metal shells.

These materials can not only resist UV erosion, but also withstand various chemical corrosion and extreme weather conditions such as hot, cold, and humid environments. By using these high-performance materials, the combiner box can maintain structural integrity and functional stability, thereby providing long-term and stable power output for the solar system.

Yes, improper wiring may cause the PV combiner box to overheat, reduce efficiency, and may even pose serious safety hazards. To ensure the efficient and safe operation of the solar system, it is necessary to ensure that all electrical connections are very secure and meet the rated voltage and current requirements of the system. Correct wiring not only optimizes the transmission efficiency of electrical energy but also prevents electrical failures caused by poor wiring, thereby ensuring the stability and safety of the entire system.
Regular inspection: Check the DC combiner box every few months to ensure that all connections are tight and not loose. Loose connections can cause poor contact and increase the risk of overheating and fire.
Keep it clean: Remove dust, dirt, and other impurities from the inside and outside of the combiner box. This helps prevent short circuits and corrosion, especially in wet or dusty environments.
Waterproof and sealing inspection: Check whether the sealing and waterproofing measures of the combiner box are intact. Any cracks or damaged seals should be repaired immediately to prevent moisture from penetrating.
Check protective devices: Check that fuses and circuit breakers are working properly. These are important safety devices in the combiner box, which can cut off the current when the current is too large to prevent equipment damage.
Check for corrosion: Regularly inspect terminal blocks and metal parts for signs of corrosion. Corrosion can lead to poor contact, reducing the overall efficiency and safety of the system.
Monitor system performance: Pay attention to whether the output of the system drops, which may be a sign of DC combiner box failure. If you notice performance degradation, you should conduct a more in-depth inspection.
If you are not familiar with electrical systems, it is recommended to ask professional technicians for regular inspection and maintenance. Professionals can identify and resolve problems that may not be readily apparent.
Following these maintenance steps can help ensure that your PV combiner box and entire solar system operate safely and efficiently. Not only can it extend the life of the equipment, it can also improve the overall performance of the system.

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