Certification requirements and compliance testing of combiner boxes

In modern photovoltaic systems, combiner boxes (also called photovoltaic combiner boxes or DC combiner boxes) are one of the key components that provide the function of combining the current of multiple photovoltaic arrays in series. For the long-term and safe operation of this system, combiner boxes need to meet certain certification requirements and compliance testing. The following will explore this topic in depth.

1. Importance of combiner boxes

The role of combiner boxes in photovoltaic systems is not limited to simple current collection. It has multiple functions such as simplifying wiring, reducing loads, and providing overload protection and short-circuit protection. Because it is located in a key position between the photovoltaic system and the inverter, any failure may cause power outages or cause safety accidents. Therefore, its reliability and safety are crucial, which is the significance of certification and compliance testing.

2. Common certification standards

The certification of combiner boxes usually involves multiple international and regional standards to ensure the reliability and safety of products in practical applications. Here are some common certification standards:

IEC 61439

This is an international standard for low-voltage switchgear and controlgear groups, covering the design, manufacturing and testing requirements of the equipment. Including technical requirements in many aspects such as temperature rise, dielectric strength, short-circuit withstand and shielding level.

UL 1741

This standard covers the safety requirements for grid-connected photovoltaic system equipment used in North America. UL 1741 focuses on ensuring that the equipment correctly switches and cuts DC and AC currents, and provides guidelines for overvoltage and surge protection.

TUV Rheinland Certification

TUV Rheinland certification indicates that the product meets European safety, quality and sustainability requirements, especially for photovoltaic modules and related equipment. TUV tests include environmental tolerance, electrical safety, mechanical strength, etc.

3. Compliance test content

The compliance test of the combiner box covers all stages from product design to factory testing. Mainly involves the following aspects:

Electrical testing

Electrical testing includes insulation resistance testing, withstand voltage testing, ground continuity testing, etc. These tests ensure the safety of the combiner box under different voltage and current conditions.

Thermal performance testing

Thermal performance during normal operation is particularly important for the long-term reliability of the combiner box. This test evaluates the heat rise and heat dissipation capabilities of internal components to avoid failures caused by overheating.

Mechanical strength testing

Since the combiner box is usually installed outdoors and needs to withstand the test of sunlight, wind and rain, the mechanical strength test includes the ability to resist impact, vibration and pressure, as well as the durability test of the shell.

Environmental adaptability testing

Environmental testing includes performance under conditions such as salt spray, damp heat, low temperature and high temperature, ensuring that the combiner box can still operate efficiently under different climatic conditions.

4. Production compliance management of combiner boxes

In order to ensure that products continue to meet standard requirements, companies need to establish a complete production compliance management system. Here are some key measures:

Supply Chain Management

Select qualified suppliers and high-quality materials to ensure that each component meets the standards from the source.

Production Process Control

Through automated equipment and information systems, real-time monitoring of every link in the production process ensures the consistency and stability of the product throughout the production process.

Internal Audit and Improvement

Regularly conduct internal audits of the quality management system and product quality to continuously improve the process and product quality to ensure that each batch of products can meet the factory standards.

5. Conclusion

As an important component of the photovoltaic system, the quality and performance of the combiner box directly affect the stability and safety of the entire system. It is an important responsibility of every manufacturer and supplier to ensure its effectiveness and reliability in actual applications through strict certification requirements and compliance testing. Doing a good job in the certification and compliance testing of the combiner box can not only improve the market competitiveness of the product, but also provide users with safer and more efficient energy solutions.

Through scientific control and refined management of the above links, the combiner box can play its maximum role in the photovoltaic system and contribute to the popularization and application of green energy.