How to Prevent Solar Rooftop Fires with an Arc Fault Circuit Interrupter?

While fires related to rooftop solar panels are rare, they are also extremely dangerous because they can spread rapidly, consuming entire homes before first responders arrive to put them out.

The majority of PV plant fire accidents are caused by DC arcing.

Fortunately, you can protect your home and your family from this deadly threat with an Arc Fault Circuit Interrupter (AFCI), which will shut down any circuit with an electrical irregularity.

This blog will discuss the prevention of Solar Rooftop Fires with an Arc Fault Circuit Interrupter. Read on to learn more!

What do you need to know about arc fault circuit interrupters?

An arc-fault circuit interrupter (AFCI) or arc-fault detection device (AFDD) is a circuit breaker that shuts down the circuit when it identifies electric arcs. They are designed to detect and break electrical currents.

Unlike conventional circuit breakers, Arc Fault Circuit Interrupters distinguish between a ‘harmless’ arc, which occurs during everyday use (such as the movement of a switch or plug), and one that could cause a fire (such as an open wire in a lamp cord).

What is an arc fault?

An arc is a glow phenomenon caused by the ionization of air when an electric conductor is close to another conductor (or ground), and the voltage between them breaks down the air.

An arc produces high temperatures and sometimes can result in open flames. In an electrical system, arcs not only cause the surrounding insulation materials to break down or carbonize and become ineffective, but they can also easily ignite nearby materials.

In a PV system, arcs may be caused by loose terminals, poor contact, broken cables, aging, carbonized, or damaged insulation materials, or damp and corrosive wires. Electric arcs are likely to occur as there are many wiring terminals on the DC side of the PV system.

Bearing all of this information in mind, it’s important to have AFCIs feature on rooftop solar installation.

The Function of Arc Fault Circuit Interrupter

An AFCI is a safety device that monitors the current flow through it. It detects abnormal situations such as arcing or short circuits, and once this happens, it trips its internal contacts – stopping all power from flowing so that there is no chance of any fires occurring.

To detect an arc, look for spikes at a certain frequency and too many discontinuities. A mismatched waveform is also a giveaway – one that doesn’t repeat itself periodically.

Frequency (the number of times per second) and amplitude (the height or depth of a peak) are two important things you need to keep an eye out for when detecting an arc.

An Arc-Fault Circuit Interrupter should not trip during normal conditions. AFCI electronics allow the system to operate if there is a current surge. They also use thermal, instantaneous, and load current sensors; all types of sensors have been shown to work in different situations.

How to prevent rooftop PV fires?

Arc fault circuit interrupters are the latest evolution in protecting homes from devastating fires caused by electrical shorts and faulty wiring. As you can see, AFCI protection can be an absolute lifesaver for anyone living in a home or building with solar panels.

Solarstone only uses inverters that have AFCI feature to ensure maximum protection for your home and solar system. It is essential that comprehensive measures are employed, especially intelligent arc detection and rapid shutdown technologies, in order to improve the safety and control level of PV plants.