Press Releases

TSUN Module-level Rapid Shutdown obtains UL Certification

Build a Security Firewall for PV Power Stations


Recently, TSUN Module-level Rapid Shutdown successfully obtained UL certification of the United States, which means that the safety of TSUN Module-level Rapid Shutdown has been authoritatively recognized, and TSUN has the ability to provide safe and efficient rapid shutdown solutions to the United States and North America in accordance with UL standards.

Fast Shutdown is a concept proposed by the National Electrical Code (NEC) to ensure the safety of PV systems. In 2014, NEC issued the NEC2014 690.12 " Module-level Automatic Shutdown Solution " standard, which explicitly required the rapid shutdown function of PV systems. In 2017 NEC690.12, there are more stringent requirements for rapid shutdown —— the distance to the PV matrix is 305mm, which as the limit. Within 30 seconds after the rapid shutdown device is started, the DC voltage outside the limit is reduced to below 30V, while in the limit range is reduced to below 80V.


Fire is the main safety risk faced by PV power stations. When the PV system catches fire, DC high voltage still exists, which threatens the safety of firefighters. However, if installed the module-level rapid shutdown, firefighters can quickly cut off the connection between the modules and rescue the power station.

TSUN Module-level Rapid Shutdown solutions are designed by NEC 2017-2020 standard and compatible with SUNSPEC, which can work with all solar inverters that even has SUNSPEC. As for the fire safety of solar rooftops and buildings, TSUN Module-level Rapid Shutdown could shutdown DC high voltage under 30V immediately, which protects both the building safety and personal safety of firefighters.


TSUN Module-level Rapid Shutdown also has more features as the follows:

  • 80V input DC voltage (UL standard)/120V input DC voltage (EU standard) both one DC input TSOL-RSDM-DS and two DC input TSOL-RSDM-DD available

  • Over 85°C temperature protection automatic shutdown and multiple manual shutdown methods.

  • 20A input current, compatible with both 182mm and 210mm panels.

  • PLC communication, plug and play, easy installation.

The United States is the first country in the world to impose mandatory requirements for rapid shutdown, and it is also the country with the most stringent standards and requirements. UL is an authoritative organization engaged in safety testing and appraisal, and has extremely demanding requirements for product safety and reliability. TSUN has obtained UL certification, demonstrating the strength of TSUN Rapid Shutdown in terms of safety and reliability, which is the recognition of the advanced technology and excellent quality of TSUN Rapid Shutdown by the international authority.

TSUN always insists to adopt the latest safety technology and requires that the design and production of products must strictly comply with the corresponding safety standards. It is believed that in the future, TSUN Rapid Shutdown will be increasingly used in PV systems to build a "Security Firewall" for PV power stations.