EXCB1-DC6-2 – 6 In 2 Solar PV Combiner Box

EXCB1-DC6-2 6 In 2 Out PV Combiner Box – Maximum Capacity with Dual MPPT Protection

The EXCB1-DC6-2 6 in 2 out PV combiner box from HUYU Electric is the largest-capacity model in the EXCB1 series, designed for large-scale commercial and residential photovoltaic installations. This advanced box consolidates up to six independent DC input strings into two output pairs, making it a perfect match for dual MPPT inverters or parallel inverter configurations managing multiple string arrays. Each output pair is protected by a 40A DC Max Circuit Breaker, ensuring robust overcurrent and short-circuit protection for every string in its grouping. The integrated Type 2 Surge Protective Device (40kA Imax) provides comprehensive lightning protection for the entire system.

The EXCB1-DC6-2 features a durable IP65 and IK10 rated PC/ABS enclosure, making it suitable for harsh outdoor environments. With CE, TUV, and CB certifications, it adheres to demanding international safety standards. The pre-wired design with clearly labeled terminals and versatile cable entry options enables swift and accurate installation. Moreover, HUYU Electric offers factory-direct OEM/ODM solutions with private labeling and full documentation to support distributors and EPC contractors in managing large PV projects.

Technical Specifications – EXCB1-DC6-2

Efficient Wiring for Large-Scale PV Installations

Managing six strings in a commercial solar project can become a wiring challenge. The EXCB1-DC6-2 6 string solar combiner resolves this by consolidating multiple combiner boxes into one centralized unit, reducing cable clutter and simplifying the overall system design. Instead of using two separate 3-string combiner boxes, installers can achieve greater efficiency in time, space, and cost by utilizing a single EXCB1-DC6-2. Its larger Pg25 output ports (6–10 mm²) accommodate heavier cables essential for higher combined currents, while resettable 40A MCBs provide enhanced system protection and minimize downtime associated with replacing fuses. The pre-wired, clearly labeled inputs and outputs ensure minimal wiring errors onsite and faster installation times.

OEM/ODM Supply – 6-String Combiner Boxes for Commercial PV Systems

Buyer’s Guide

How to Select a 6-String Combiner Box for a Dual MPPT Inverter

Key considerations for selecting the EXCB1-DC6-2 in large-scale photovoltaic installations.

1. When Six Inputs Are the Right Fit

The 6-string combiner box is an excellent choice when your configuration includes six parallel strings connected to two MPPT inputs on a dual inverter. This approach ensures optimal energy yield by independently optimizing strings for different orientations, such as south- and west-facing arrays.

2. Why Upgrade to 40A MCBs?

Equipped with 40A DC MCBs, the EXCB1-DC6-2 supports higher currents, especially for high-efficiency or bifacial solar panels with elevated Isc ratings. It minimizes nuisance tripping during peak irradiance and ensures compliance with electrical codes.

3. Breaker-Type Protection for Easy Maintenance

DC MCBs enable convenient maintenance by allowing trips to be reset with a single switch, eliminating the need for time-consuming fuse replacements. If specific codes require visible isolation gaps, opt for the EXCB3-DC6-2 isolator-type variant.

4. Cable Management and Output Sizing

The box provides six Pg09 input ports accommodating 2.5–4 mm² cables and two larger Pg25 output ports for 6–10 mm² cables, allowing safe transportation of combined higher currents. Ensure output cables are correctly sized for total Isc and meet the 1.25 safety margin.

Frequently Asked Questions

Is a solar combiner box necessary for a 6-string PV system?

Absolutely. A solar combiner box is not just necessary but critical for the safety and code-compliance of a 6-string PV system. Without it, you would have six uncoordinated strings entering the building, with no centralized overcurrent or surge protection. The EXCB1-DC6-2 6 in 2 out PV combiner box provides this essential safety hub, organizes the wiring, and offers a single point for maintenance disconnection, which is a fundamental requirement of all major electrical codes.

Does a solar combiner box increase the voltage?

No, a solar combiner box does not increase voltage. It combines multiple string inputs in parallel. In a parallel connection, the voltage remains constant and equal to a single string’s voltage, while the total current is the sum of the currents from all strings. For example, three strings each producing 400V at 10A will combine to an output of 400V at 30A. Voltage is only increased by connecting panels or strings in series. Understanding this distinction is key to correctly sizing your inverter and cabling.

What does a combiner box do for solar panels?

A combiner box for solar panels acts as the central nervous system for the DC side of a PV array. It merges the power from multiple strings, provides individual overcurrent protection for each string via DC breakers or fuses, and houses a surge protective device to protect the inverter from lightning strikes. It also serves as a crucial manual disconnect point. The EXCB1-DC6-2 breaker type solar combiner performs all these functions for up to six strings, with its dual-output design preserving the independent MPPT tracking capability of a modern dual-input inverter.

What is the difference between a 6-in-1-out and a 6-in-2-out combiner box?

The difference is in the output configuration and the type of inverter it serves. A 6-in-1-out PV combiner box combines all six strings into a single DC output, designed for a single-MPPT inverter. A 6-in-2-out combiner like the EXCB1-DC6-2 splits the six strings into two independent output groups. This is specifically designed for dual MPPT inverters, allowing two groups of strings to be optimized independently. For example, you could have one group of three strings facing east and another three facing west, with each group tracked by a separate MPPT to maximize the total energy harvest.

“`