Brief Introduction about Solar Module Level Rapid Shutdown

People talk about the rapid shutdown more and more often if you are learning about the solar PV industry.

You may have a question come to your mind.

What is rapid shutdown?

Rapid shutdown is an electrical safety requirement and regulation for rooftop solar panel system by the National Electrical Code (NEC) in USA. A precaution to fast switch off the solar system DC conductors by mechanical. To reduce fire and improve firefighter safety on solar rooftops.

Rapid shutdown was first introduced in the 2014 NEC section 690.12, PV system conductors outside the green areas are required to be controller via rapid shutdown. No more than 30V and 240 volt-amperes within 10 seconds of rapid shutdown initiation.

Conductors impacted by NEC 2014 rapid shutdown requirements
Conductors impacted by NEC 2014 rapid shutdown requirements

Newer regulation, NEC2017 rapid shutdown needs to occur at the individual solar modules, rather than at the solar array level.

The rapid shutdown boundary limited in 1 feet, all the DC strings inside array boundary must be less than 80V with 30 seconds of rapid shutdown initiation. The dc strings outside of array boundary must be less than 30V within 30 seconds of rapid shutdown initiation.

NEC 2017 rapid shutdown requirements
NEC 2017 rapid shutdown requirements

There are many inverter systems are inherently compliant with module-level rapid shutdown (NEC2017 NEC2020) on their own, like the micro-inverter and optimizer system with built-in rapid shutdown function.

If you install a string inverter system, you may also need to install module-level power electronics to comply with NEC2017 or NEC2020.

Why the rapid shutdown is important ?

The solar rooftops system is am important capacity for solar PV industry.

Qualify solar rooftop installation calls the safety of solar building and solar owner.

It’s good idea to have more solar power, and it is important to keep the solar buildings safe period the decades of solar system working life.

For a solar PV system, when the sun is shining, and the solar rooftop is in proper working order. But in certain emergency situations,those high voltage DC conductors will remain live and energized even though the firefighters have shut down power to the building. Without rapid shutdown and mechanical cut-off at panels, firefighters will have a risk of high voltage DC electric shock even they wear insulated clothing that offers protection.

Another important thing is that rapid shutdown reduce the solar fire

solar panel fire

Most of the solar fires are cased by DC arc fault happens in solar DC circuits, the key of reduce solar fire is about preventing the dc arc fault in solar installation and cut-off the dc power to stop dc arc before solar systems get fire.

Micro-inverters, DC optimizer systems and the module level rapid shutdown devices that reduce the dc voltage to safe levels in the event of a fault. All the solutions is developed for prevent solar fires caused by dc arc faults.

Our solution

As a manufacturer who is concentrating to offer cost-efficiency solar electric components and protecting solutions, BENY electric keeps the innovation developing on solar safety.

A module level rapid shutdown solution which is popular in many countries. The rapid shutdown solution is one of our cutting-edge solutions. The RSD works with most of string inverters and panels.

Module Level Rapid Shutdown快速切断
Module Level Rapid Shutdown BFS-11


*Versions for 1 panel, 2 panels and 4 panels.

*Shutdown the solar panels to 0V at micro-seconds

*With emergency button switch for manual shut down the high dc voltage

*Automatic shutdown the DC power once AC power loss

*Automatic shutdown the DC power when high temperature up to 85 is detected

*No cross-talk with inverter or WIFI

*25 years warranty

bfs 11 wiring

More module level power electronics and solutions from BENY electric is COMING SOON.

coming soon

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