| Work Detail |
Brazil’s National Institute of Metrology, Quality and Technology (Inmetro) says it has introduced a requirement for inverters to have arc fault circuit interrupters, effective December 2024, to prevent fires and enhance PV system safety.
Solar inverters in Brazil must include arc fault circuit interrupters (AFCIs) from Dec. 1, according to new rules from Inmetro.
Several distributors have reportedly begun selling non-compliant inverters at low prices, sources told pv magazine. This creates unfair competition with companies that have already updated their products and could lead to losses for customers unaware of the mandatory protection devices and upcoming fire inspections after the deadline.
Leandro Michels, coordinator of the PV inverter testing laboratory at the Smart Grids Institute (INRI) of the Federal University of Santa Maria (UFSM), said manufacturers should not rely solely on Inmetro’s requirements.
“Inmetro’s ordinance provides a period for products without AFCIs to still be marketed, but this does not mean that the Fire Department will accept new buildings without protection,” he said. “Evaluating the product is one thing, implementing it is another, and the fire department has the prerogative to state whether or not a product can be used, from an electrical safety point of view. Therefore, they can create stricter rules, even for products that can be sold.”
Northern Electric and Power (NEP) has prepared for the new regulations. NEP Sales Director Marcus Serrano explained that, unlike other major distributors in the market, the company did not need to sell off stock of inverters without the AFCI device.
“At the beginning of next year, these devices will not even be able to be sold, and the installers who acquired them for the stocks will have a lot of work to do to adapt, unfortunately,” said Serrano.
The standard requiring the inclusion of AFCI in photovoltaic systems has moved from regionalization to national standardization. Initially, several states, including Mato Grosso, Minas Gerais, and Goiás, implemented their own regulations focused on fire safety, particularly in commercial and industrial buildings.
The National Council of Military Firefighters of Brazil (Ligabom) played a key role in unifying these regional initiatives. In 2022, discussions began on making this protection mandatory at the national level, leading Inmetro to adopt the technical standard through Ordinance 140/2022 to enhance safety in photovoltaic installations across the country.
Consequences of non-compliance
Non-compliance with the new standards can lead to serious consequences. For installations that require fire department permits, such as large plants, businesses, and industries, the absence of AFCI can result in failed inspections, preventing the renewal of licenses like the Fire Department Inspection Report (AVCB) or the Certificate of Conformity (CERCON).
Consumers who purchase equipment without AFCI protection may incur additional costs for future modifications if their systems require adjustments during inspections.
The results of the homologation tests for inverters with AFCI indicate that there is still much work to do. According to INRI technical consultant Ricardo J. F. Bortolini, one laboratory in Brazil found that only 18% of the products passed the initial test, while 64% passed after adjustments. He emphasized the importance of equipment certification, laboratory accreditation by Inmetro, and the necessity for local inspections.
Elgin Solar Director Glauco Santos noted the growing demand for equipment that complies with the new standard.
“Our network of installers is always attentive to market changes and demands. As a result, we have noticed a significant increase in the demand for inverters with AFCI protection mechanisms,” he said. “Our R&D department has already been working on adapting our inverters to meet the requirements of Inmetro and the fire department.”
Levi Santos Cidral Junior, the solar GD Engineering coordinator for Brazilian inverter maker WEG, said that the company had anticipated this market need.
“We have had options for photovoltaic inverter lines with AFCI included as standard for a few years now, as we know that even if it is not mandatory, it is still very important to provide access to the technology,” he said. “This old inclusion was already part of a movement to include it in the entire line. The mandatory requirement by Inmetro is finally coming, and now we have 100% of inverters with AFCI.”
WEG Solar and Building Director Harry Neto said that concerns about safety should be a priority for manufacturers, as they already are in other sectors.
“Even our smallest microinverters were tested at the ordinance to ensure that there is no formation of an electric arc,” he said. “Buying equipment that does not comply with the standard will be equivalent to buying a car without a seatbelt.”
Equipment risks
Beyond bureaucratic and financial concerns, the AFCI serves a critical role in detecting and interrupting electric arcs, which are a leading cause of fires in photovoltaic installations. As Brazil experiences exponential growth in solar energy adoption, incidents of fires related to photovoltaic systems have also risen, highlighting the need for more robust protection mechanisms. The AFCI can detect an electric arc in the system and interrupt it before it escalates into a more dangerous situation, such as a fire.
“In a traditional system, if you need to perform maintenance, you turn off the inverter. However, the voltage level between the inverter and the modules remains high, and it is not possible to turn it off,” said Juliano Pereira, Brazil country manager for Israel-based inverter maker SolarEdge. “This voltage level creates a risky environment for people. In the event of a fire, the level is so dangerous that even the Fire Department has difficulty responding. In the case of the SolarEdge solution, we always offer a safe voltage level. Therefore, even if there is a change in legislation, our system is prepared for it.”
To address this issue, the manufacturer provides its power optimization technology, which enables the modules to operate independently. This technology ensures greater generation and improved visibility for asset management, thereby reducing losses and costs.
Rapid shutdown?
Another relevant standard is rapid shutdown (RSD), which many Brazilian states are considering as an additional safety solution.
One issue with a photovoltaic system is that it generates electrical voltage as long as light shines on the panels, even if the inverter or utility grid is turned off. This poses risks for maintenance and firefighting.
RSD can reduce the electrical voltage generated by the panels in emergencies, effectively “turning off” the panels and lowering the risk of electric shock for firefighters and rescue teams. Currently, RSD is not mandatory nationwide, and its implementation depends on regional standards. States like Goiás already require RSD in commercial and industrial systems to obtain the AVCB/CERCON, while others are evaluating its adoption.
Ligabom has not yet commented on standardizing rapid shutdown nationwide. “The safety systems are complementary to each other. In other words, both AFCI and rapid shutdown are necessary for issuing the AVCB in businesses, industries, and large plants,” Captain da Costa stated.
Compliance with these standards is a necessary step forward for Brazils photovoltaic market, ensuring the safety of installations and protecting everyone involved in the operation and maintenance of solar systems.
Recommendations for consumers
Isabelle Sene, a technical and regulatory specialist at the Brazilian Association of Photovoltaic Solar Energy (Absolar), said that consumers should seek trustworthy companies with strong reputations that adhere to safety and quality standards.
These companies should be accredited by the Regional Council of Engineering and Agronomy (Crea) and, if possible, associated and certified by the entity. The equipment must display the Inmetro seal and include information about safety devices on the datasheet.
“Consumers should not change the electrical installation or the configuration of the equipment on their own, under any circumstances. All procedures must be performed by specialized technicians, preferably authorized by the companies supplying the equipment,” said Sene. “For consumers who need to make changes to their projects, they can first check whether their equipment already has such devices and seek out qualified companies for changes and adaptations to the project, keeping in mind that adaptations are essential for life safety.” |
