Arc faults are one of the few solar fire risks that regular breakers can’t see. A loose MC4 connector or a nicked conductor can arc for minutes (sometimes hours) without tripping a standard overcurrent device, because the current never actually exceeds normal operating levels.
That’s the exact gap an Arc-Fault Circuit Interrupter (AFCI) is built to close: it listens for the high-frequency signature of an arc and shuts the string down before it ignites.
For distributors and installers alike, selecting an inverter without the required AFCI functionality can mean a failed grid-connection application, a rejected fire department inspection, or a shipment that simply can’t clear customs paperwork.
This guide explains where AFCI is currently mandatory, where it remains optional, and how these regulations should influence your inverter selection.
Global Compliance Map: Quick Reference
| Market | Governing Regulation | Mandate Status | Applies To |
| United States | NEC 690.11 | Mandatory | PV systems on or in buildings operating at voltage 80 V or greater |
| Canada | CE Code Rule 64-216 | Mandatory | DC PV source/output circuit voltage at 80 V or greater |
| Brazil | INMETRO Ordinance 515/2023 | Mandatory | Qualifying PV inverters sold/certified in Brazil |
| European Union | No bloc-wide rule | Not a blanket EU mandate | Varies by member state/project |
| United Kingdom | BS 7671 Reg. 421.1.7 | Not PV-mandated | Certain socket circuits in high-risk residential buildings |
| Australia / New Zealand | AS/NZS 4777, AS/NZS 5033 | Not yet mandated | PV installations |
Now let’s go market by market.
United States
The US was the first country to legally require AFCI on solar, and it remains the strictest. NEC 690.11 requires a listed DC arc-fault circuit interrupter on any PV system installed on or within a building operating at 80 volts or more. The device has to detect the fault, interrupt it, and visually indicate that it tripped, and it must be certified under UL 1699B, the listing standard for PV DC arc-fault circuit protection.
Canada
The Canadian Electrical Code (CSA C22.1), Rule 64-216, requires DC arc-fault circuit protection on any PV source or output circuit calculated at 80 V or more, functionally the same trigger voltage as the US rule. But the device has to detect and interrupt the fault, lock out automatically rather than self-reset, and visually indicate that it tripped, and it must carry CSA C22.2 No. 292 certification, which is Canada’s own DC-AFCI standard.
Brazil
In Brazil, INMETRO Ordinance 515/2023 requires inverters above 120 V with input (short-circuit) current up to 20 A to include arc-fault protection; units below that threshold must undergo a test, and if they sustain an arc, AFCI is required for them too. The ordinance took effect on December 1, 2023, with a 12-month adequation period, making AFCI mandatory for inverters manufactured or imported in Brazil from December 1, 2024.
European Union
As of now, the EU has no union-wide legal mandate for AFCI on residential or commercial PV. The relevant technical groundwork exists: IEC 63027 was published in 2023 with input from Germany’s Fraunhofer ISE specifically to give the industry a better real-world arc-fault test than UL 1699B. But adoption into binding EU or national electrical codes hasn’t happened.
United Kingdom
The UK doesn’t have a solar-specific AFCI law either. BS 7671 (the IET Wiring Regulations), currently at Amendment 4 (2026), does mandate Arc Fault Detection Devices under Regulation 421.1.7, but only for single-phase socket-outlet circuits up to 32 A in high-risk residential buildings (over 18 m or six storeys), HMOs, purpose-built student accommodation, and care homes.
Australia & New Zealand
Australian and New Zealand installations run under AS/NZS 4777 (grid connection) and AS/NZS 5033 (PV array installation and safety). Neither currently mandates AFCI. Notably, the 2014 edition of AS/NZS 5033 explicitly acknowledged that arc-detection technology was still immature at the time of writing and flagged that a future revision would likely require it once the technology matured.
What Should Distributors and Integrators Know
When sourcing solar inverters, distributors and system integrators should consider not only current regulations but also the direction of future safety standards.
In markets where AFCI compliance is mandatory, supplying products that meet the applicable regulations is essential. Failure to comply may prevent a PV project from passing inspection, delay commissioning, or restrict market access.
For example, in the United States and Canada, qualifying PV systems must include DC arc-fault protection under the applicable electrical codes. Choosing inverters with integrated AFCI functionality helps ensure system compliance.
In Brazil, AFCI is a product-level requirement, meaning solar inverters must incorporate AFCI functionality to comply with INMETRO regulations.
The European Union, the UK, Australia, and New Zealand do not currently require AFCI for solar PV systems by law. However, this does not mean AFCI is unimportant.
European markets are known for their high safety expectations, and many installers, EPCs, and project owners increasingly view AFCI as a desirable safety feature. Offering inverters without AFCI may reduce product competitiveness and make it harder to meet customer expectations in these markets.
Meanwhile, Australia and New Zealand have already acknowledged in AS/NZS 5033 that arc-fault detection is likely to become a future requirement as the technology matures. As global fire safety standards continue to evolve, sourcing AFCI-equipped inverters today helps distributors prepare for future regulatory changes while offering customers a safer and more future-ready solution.
Which Supplier Provides Solar Inverters with AFCI Functionality
At Ktech Energy, safety is integrated into our inverter design. Our residential and commercial solar inverters are available with built-in AFCI technology that continuously monitors for arc faults and disconnects the affected circuit before an electrical fire can develop.
Combined with high conversion efficiency, multiple MPPT configurations, and comprehensive protection features, our AFCI-enabled inverters help distributors and installers meet evolving market expectations while providing safer, more reliable PV systems for end users.
Whether you’re supplying residential rooftops or commercial solar projects, we can help you select the right inverter solution for your target market and local compliance requirements.
Contact our team today!
