What is a Solar PV Combiner Box?

    The role of the solar PV combiner box is to bring together the output of several solar strings. The conductors of each string land on a fuse terminal, and the output from the fuse input are combined into a single conductor that connects to the solar combiner box and inverter. Once you have a DC combiner box in your solar project, there are usually some additional features incorporated into the combiner box, Such as isolating switches, monitoring equipment and rapid shutdown devices.

    The solar DC combiner box also integrates the incoming power into a main feed that is distributed to the PV inverters. This saves labor and material costs by reducing wire. DC combiner boxes are designed to provide overcurrent and overvoltage protection to improve the protection and reliability of the inverter.

    If a project has only two or three strings, such as a typical home, a solar string combiner box is not required. Instead, you will need to connect the strings directly to the inverter. PV string combiner boxes are only necessary for large projects, from 4 to 4,000 strings. However, photovoltaic combiner boxes have advantages in projects of all sizes. In residential applications, PV combiner boxes can bring a small number of strings to a central location for easy installation, disconnection and maintenance. In commercial applications, combiner boxes of different sizes are often used to draw power from unorthodox layouts in different building types. For utility-scale projects, combiner boxes allow site designers to maximize power and reduce material and labor costs by distributing combined connections.

    The solar panel combiner box should be located between the solar panels and the inverter. It limits power loss when optimally positioned in the solar array. Location is very important, as solar combiner boxes in non-optimal locations can add to DC BOS costs due to voltage and power losses, and while it’s only a few cents per watt, it’s important to figure it out.

    Solar PV combiner boxes require little maintenance, and the environment and frequency of use should determine the level of maintenance. It’s a good idea to check them regularly for leaks or loose connections. If the PV combiner box is installed correctly, it can continue to function throughout the lifetime of the solar project.

    Quality is the most important consideration when choosing a DC solar combiner box, especially since it is the first piece of equipment connected to the output of a solar panel. DC combiner boxes are not expensive compared to other equipment in a solar project, but a faulty combiner box can fail in dramatic ways, including spewing fire and smoke. All equipment should be third-party certified to comply with the relevant standard for this type of equipment, UL1741, and be sure to choose a solar combiner box that meets your project’s technical requirements.

    A new trend is adding a length of cable with a PV connector on the end. Rather than having the contractor drill holes in the pv array combiner box and install the fittings on site, the solar cable can be installed at the factory, allowing the installer to simply connect the output conductors to the array combiner box using the mating PV connectors.

    Depending on the application, PV string combiner boxes are equipped with monitoring devices that measure current, voltage and temperature to ensure string availability and maximize power generation. The subsystems formed by solar string combiner boxes can be standardized according to the number of strings, voltage and current rating. Slocable offers different series of solar combiner boxes, each of which is dedicated to specific installation conditions with typical configurations.

The Advantages of Solar PV Combiner Boxes:

1. The PV solar combiner box improves the safety of the solar panel and the entire PV power plant.
2. Photovoltaic combiner boxes, also known as DC switchboard, are factory assembled with monitoring equipment, DC fuses, surge protection devices and disconnect switches as a plug-and-play solution.
3. Different housing sizes for flexible coverage of up to 32 strings.

Features of Solar DC Combiner Box:

1. Factory-assembled combiner box solution for all residential, commercial and utility scale applications, 1000V and 1500VDC in single string or up to 32 strings; monitoring optional.
2. The DC combiner box adopts Gemini thermoplastic outdoor box, which has excellent mechanical strength.
3. Due to the mechanical properties of the combiner box, it is protected from dust, sea or strong water column, chemicals and strong UV rays: IP66, IK10 and GWT 750°C.
4. Electrical characteristics: Double insulation (Class II), Ui/Ue: 1000V DC/1500V DC.
5. Depending on site conditions, Gemini enclosures can be floor-mounted or wall-mounted.