Arc Fault Switch: The Key Technology for PV System Safety Upgrades

The photovoltaic (PV) industry is growing rapidly. Whether it’s a large-scale power station covering hundreds of acres or a commercial PV system on a shopping mall rooftop, "safety" is the top concern—especially electrical fires, which are like a "bomb" hanging over the system. Now, with the Arc Fault Switch (also known as an AFCI Circuit Breaker), a device specifically designed to address this "fire hazard," it has become a critical component for ensuring PV system safety. Today, we’ll explain what this device is and why it’s a must-have for any PV installation.

First, Understand: What Is an Arc Fault Switch (AFCI Circuit Breaker)?

Simply put, it is a "special switch for preventing arc-induced electrical fires." In a PV system, if wires age, connectors loosen, or insulation is damaged, current will "jump" irregularly, forming an electrical arc—this arc reaches extremely high temperatures, can generate sparks in seconds, and ignite nearby wire insulation or thermal insulation cotton, leading to a fire within minutes.

What Benefits Does an AFCI Circuit Breaker Bring to PV Systems? 4 Practical Advantages!

1. Accurate Arc Detection—Outperforming Traditional Devices

Traditional circuit breakers and fuses can only protect against overloads and short circuits; they are completely "blind" to DC arc faults in PV systems. Due to the unique signal frequency of DC arcs, traditional devices cannot identify them—by the time a problem is detected, a fire has already started.

However, AFCI circuit breakers use advanced arc detection technology. They can accurately identify both series arcs (e.g., sparks from broken wires) and parallel arcs (e.g., sparks from two wires touching), with no missed or false detections. This fundamentally eliminates fire hazards at the source.

2. "Dual Protection" for PV—No Fear of DC Arcs

PV systems operate on DC power, which differs from the AC power used in households: AC power has a "zero-crossing point," meaning arcs tend to extinguish on their own. But once a DC arc forms, it is like being "stuck"—it will not extinguish spontaneously. Its temperature rises rapidly, making the fire risk far higher than that of AC arcs.

AFCI circuit breakers are specifically designed for DC arcs. They monitor the circuit 24/7, and as soon as an arc appears, they cut off the power supply immediately. Whether it’s the wiring of rooftop PV panels, combiner boxes, or inverters in a power station, there’s no need to fear fires caused by DC arcs—protecting equipment, buildings, and personnel safety.

3. Remote Monitoring—Saving Significant O&M Effort

Today’s high-quality AFCI circuit breakers can connect to intelligent monitoring systems. For example, Fonrich’s AFCI can link to the SafeSolar cloud platform: O&M technicians can open a computer in the office or use a mobile app to check the system status in real time—whether there’s an arc alert, which circuit has a problem, and whether the current is stable, all at a glance.

If a fault occurs, a notification is sent directly to the technician’s phone—no need for daily on-site inspections. For instance, if an arc occurs in a string, the team can directly locate and repair the issue based on the alert, without checking each panel one by one. This saves time, reduces power station downtime, and ultimately means more power generation (and more revenue).

4. Suitable for All Scenarios—Easy Retrofit for Aged Systems

AFCI circuit breakers can be installed in any PV setup: small residential systems, commercial projects on shopping mall rooftops, or large-scale power stations covering thousands of acres. They are particularly ideal for retrofitting aged systems—many PV installations that have been in operation for 5-6 years lack arc protection. Adding an AFCI now requires no major overhauls: Fonrich’s AFCI is directly compatible with existing inverters and combiner boxes, and installation takes only half a day, with no disruption to power generation.

Why Is AFCI a Must for PV Installations? It "Prevents Hazards Before They Occur"!

Traditional protective devices like ordinary circuit breakers are for "fault remediation"—for example, tripping only after wires have burned, by which time a fire may have already started. In contrast, an AFCI circuit breaker is "predictive": it cuts off power as soon as an arc appears, before a fire can ignite, eliminating the risk at the source.

Today, both domestic and international regulations mandate AFCI installation in PV systems—such as the NEC standard in the U.S. and China’s Code for Design of Photovoltaic Power Stations. Without an AFCI, a project cannot pass inspection. Choosing an AFCI is not just about compliance; it’s about ensuring the long-term safe operation of the power station. Cutting costs by skipping it could ultimately lead to equipment damage and unmanageable risks.

The Future of AFCI: Smarter, with "Risk Prediction"

In the future, AFCI technology will become even more advanced: It will not only "detect faults" but also use big data to predict risks. For example, if a connector repeatedly emits weak arc signals, the AFCI can send an early alert, prompting technicians to repair it before a full fault occurs. It will also integrate with inverters and energy storage systems to form a "full-system safety network," making PV systems even more reliable.

Conclusion: For PV Safety, AFCI Is Indispensable

In today’s PV industry, pursuing high power generation alone is not enough—safety must come first. The Arc Fault Switch (AFCI Circuit Breaker) is the "key line of defense" against arc-induced fires. Whether for new installations or retrofitting aged systems, choosing the right AFCI (like Fonrich’s, with accurate detection, remote monitoring, and strong adaptability) not only prevents fires and reduces O&M costs but also ensures compliance with standards, allowing the power station to operate safely for decades. As the PV industry becomes more standardized, AFCI will undoubtedly become a "standard configuration"—installing it early means peace of mind early!