Disconnecting Solar Combiner Box

The Disconnecting Solar Combiner Box contains a load-break rated, high power switch. Installers, maintenance crews, and first responders can now safely disconnect the solar array at the source.

Disconnect at the source

Installers can put the DC disconnects closer to the source. This increases safety and serviceability by de-energizing at the array.

Save space

Some roof tops and ground applications will not accept awkwardly-sized disconnects with limited mounting orientations. The disconnecting combiner not only integrates multiple components, it also increases mounting options. Designers and installers dealing with low profile racking systems or roofs with limited installation space will appreciate the space savings.

Load-break rated switch

The load-break rated switch at the heart of the disconnecting combiner is capable of breaking the circuit with sufficient speed to eliminate “arc” formation between the contacts that is common in DC circuits. The load-break rating means this switch is rated for disconnecting its full current rating for more than 6000 cycles. The switch was tested to UL508 standards and listed by CSA. This listing uniquely tests the switch for 6000 cyces at full load and ensures the switch will last for these extreme conditions.

Technology advantage

Previously, installers connected the series strings into standard solar combiner boxes placed throughout the installation for a combined homerun conductor which leads to the inverter. For increased safety and serviceability designers and engineers often include a DC disconnect switch between the combiner (with or without fuses) and the inverter. An example of this traditional method installation is shown in Figure 1.

Figure 1 - Traditional Photovoltaic DC Circuit Design.

With the new disconnecting solar combiner boxes integrated in the same system, we have achieved reduced component count, and improved DC circuit safety and serviceability. Figure 2 below shows the simplicity offered by the home run disconnecting combiner.

Figure 2 – Simplified Disconnecting Solar Combiner Solution

All disconnecting solar combiner boxes are ETL Listed to UL 1741. The load break rated switches are listed to UL 508.

Download Disconnecting Combiner Box Technical Notes

We also offer a standard non-disconnecting solar combiner box in a variety of sizes