Huawei FusionSolar’s Leading Safety Technologies for Residential PV

Analysis of previous residential PV fire accidents reveals that, regardless of the causes, DC high voltage is a direct threat, whether in construction, operation and maintenance, or even rescue efforts. In 2019, a house in Schwerinsdorf, Germany caught fire. Although more than 70 firefighters from six fire departments arrived at the scene, due to the high voltage on the roof, they had to let the house burn in a controlled manner until the solar panels were completely burnt out.

User concerns are our priority. Let's look at how Huawei FusionSolar residential PV delivers superior quality and supports firefighting safety.

Huawei FusionSolar has upgraded its optimizer to allow a rapid voltage shutdown for the safety of firefighters and maintenance personnel.

Even if the inverter is shut down, PV modules keep generating electricity as long as there is sunshine. To tackle this safety issue, Huawei FusionSolar optimizers are equipped with a module rapid shutdown function. Every module is connected to an optimizer to monitor its output. In the event of a fire, the PV rapid shutdown function can be automatically triggered by the disconnection of the inverter from the grid, interruption of communication with the remote emergency switch, or manually actuated by turning off the DC switches. As a result, firefighting measures can be taken immediately to minimize losses.

Huawei FusionSolar's safety shutdown function has been verified in a rooftop PV project on a commercial building. Two triggers were used: disconnecting the DC switch and disconnecting the AC switch. The MPPT voltage at the input of the inverter dropped to 0 V, and the shutdown time was 25s and 11s respectively, which met the requirements of the NEC 2020 690.12 standard. The safety shutdown function provides the highest level of personal safety in the industry for homeowners, installation and maintenance personnel, and firefighters.

Automatic cut-off within 0.5s in case of a fire