UL3741 Archives

June 27, 2024July 16, 2024

Better Solar Starts Here with Unirac’s UL 3741

June 27, 2024

Why is Rapid Shutdown Important?

Safety is a fundamental concern in any solar installation, and rapid shutdown is an advanced critical-safety feature that quickly de-energizes conductors in a PV array during emergencies such as flooding or fires. By disabling the power of a solar array, rapid shutdown standards protect our firefighters, first responders, and maintenance personnel from electrical hazards during emergencies. By mitigating the risk of electrocution, these systems ensure maximum protection when immediate action is necessary.

What is UL 3741?

UL 3741 is a data-driven safety standard developed to provide an alternative to Module-Level Power Electronics (MLPEs) for rapid shutdown on commercial flat roofs. While MLPEs, like microinverters and solar optimizers, have been widely used to comply with rapid shutdown requirements, UL 3741 offers a streamlined approach that caters specifically to the needs of large-scale commercial installations.

Why Should You Care?

UL 3741 matters because it protects our first responders. As an alternative to MLPEs, UL 3741 also provides a more flexible and cost-effective solution for achieving rapid shutdown compliance. By integrating UL 3741 into your solar projects, you can:

Enhance Safety: Ensure the safety of first responders and maintenance teams by adhering to stringent safety standards.
Save Money: Reduce the need for additional MLPEs, lowering overall system costs.
Streamline Installations: Simplify the design and installation process with a wide array of approved inverter combinations.

Ease of Operations & Maintenance

One of the key advantages of UL 3741 is the ease of operations and maintenance (O&M) compared to MLPEs. UL 3741 reduces the number of DC-to-DC connection potential failure points over the 25-year lifespan of the system. This translates to fewer maintenance visits, lower repair costs, and more reliable system performance over time, making UL 3741 the preferred choice for long-term sustainability.

The Unirac Advantage

Unirac is proud to prioritize safety, our first responders, and our customers. This is why Unirac offers the most extensive portfolio of flat roof, flush-mounted or tilt-up systems, and inverter combinations approved under UL 3741. Whether you’re working on a residential project with the Tesla PV Inverters, Tesla Powerwall, or a commercial installation with rail or flat roof systems, Unirac has you covered. Our solar mounting systems are designed to be application agnostic, offering compliance via both UL 3741 and MLPEs to suit your specific needs and unique use case

Comprehensive Support for Commercial Designs

Our dedicated Commercial & Industrial (C&I) team is here to help optimize your commercial designs and provide the support you need when working with AHJs, developers, or project owners. We are committed to guiding you through the UL 3741 path, ensuring that your projects not only meet safety standards but also achieve the highest levels of efficiency and cost-effectiveness.

Trust Unirac for Your Solar Mounting Solutions

At Unirac, we believe that Better Solar Starts Here. With our expertise, extensive product portfolio, and commitment to safety and efficiency, we are your trusted partner for photovoltaic (PV) mounting solutions. Let us show you the benefits of UL 3741 and why Unirac is the right choice for your next project.

For more information on how Unirac’s UL 3741 can benefit your solar installations, contact us today and discover why Better Solar Starts Here.

June 17, 2024June 17, 2024

A Conscious Approach to Pioneering Solar Mounting Engineering

June 17, 2024

Solar Mounting Engineering Expertise Matters to Customers

Solar mounting might be a technical job, but it’s a service, nonetheless. In spite of this, solar installers often underestimate the power of customer perception. This invisible force greatly impacts your business, more than you might realize, and neglecting it can have far-reaching consequences. As a result, having in-depth access to the ongoing flow within the industry becomes critical. These perceptions directly affect businesses and the industry; after all, installers act as a primary touchpoint for customers.

The power of perception becomes clear when we consider a customer who is excited about switching to solar, enticed by lower bills and environmental benefits—an ideal scenario, right? Not quite; while installing rooftop solar may appear to be a straightforward choice or even an easy decision for clients, the reality is far more complex.

According to a report by Campaign for Accountability, many solar customers feel that they receive subpar craftsmanship from solar companies, which leads to increased financial implications for them. This disconnect between the perceived benefits and the reported reality paints a worrying picture for the industry, including your business. Addressing such concerns head-on is crucial toward building trust and shaping a positive perception.

So, where do we start? There is no question that installers play a centralized role in the solar project, directly overseeing critical phases in the installation process. However, one crucial element often gets overlooked: the engineering quality of the solar mounting system. Despite accounting for a small portion of the total project cost, the racking system has an inherent function to play in the overall viability of the solar project.

Consequently, while you may pride yourself on delivering top-notch designs, layouts, and installations, it is essential to scrutinize the engineering, design, and testing standards of the solar mounting systems themselves.

Consider these compelling reasons that support the prioritization of better engineered solar mounting solutions:

Rigorous Design and Engineering for Reliability: A meticulously designed, engineered, and tested solar mounting system ensures optimal performance, long-term durability, and minimizes the risk of system failures. This translates to reliable energy generation and fewer headaches for the customer, ultimately impacting their perception of the entire project.
Cost Transcending the Initial Price Tag: While the mounting system itself represents a smaller upfront cost, its quality significantly impacts long-term expenses. A poorly engineered system can tarnish the perception of the entire solar experience, while selecting well-tested, engineered mounts safeguards the interests of everyone, from investors and homeowners to developers and installers.
Streamlined Project Execution: Quality mounting systems must be designed for smooth installation, minimizing construction time and potential errors, leading to a seamless project experience.
Investing Beyond the Minimum: Product development and testing for mounting solutions requires considerable investment in research, innovation, and resources. A ‘bare minimum’ approach by companies may lead to compromised quality and potential future issues.

Intuitive Design and Rigorous Testing Creates Better Solar for All

According to a podcast by Solar Power World, the solar industry is witnessing a trend towards smaller, lower-profile roof-mounted solar panel attachments. This shift includes a growing demand for open-channel and rail-less mounting systems, aiming for more aesthetically pleasing and potentially leak-proof installations. While such advancements may seem lucrative, they also raise certain concerns about safety and quality assurance—are testing standards used by manufacturers keeping up?

The answer, unfortunately, is not a simple yes. Existing testing procedures, designed for traditional roof settings, may not adequately assess the unique challenges posed by innovations like direct-to-deck attachments, leaving a gap in safety protocols. This gap can create potential risks if manufacturers rely solely on the bare minimum standards for testing methods.

As Ryan Estrada, technical program outreach manager at Unirac, noted, the prevailing test standards in the industry are geared towards connections into rafters, hence not fully aligning with the evolving practices of deck attachment. Common rafter-attached test standards, such as ASTM 7147 for establishing allowable loads of joist hangers and 1761 for testing mechanical fasteners in wood-based materials, exhibit limitations when applied to direct deck attachments.

Furthermore, a race toward better design and connection strength claims can be deceptive. While low-profile systems appear user-friendly, their installation can introduce new complexities that would not come to light without proper testing.

The lesson here is that controlled laboratory testing, while valuable, may not encapsulate the comprehensive safety and quality standards of the product in real-world scenarios. For instance, full-scale testing for direct-to-deck attachments conducted at Unirac’s facility revealed that solar panel roof attachment connections aren’t the only failure mode when considering the complete load path through the roof in adverse conditions. Therefore, it becomes clear that the lack of extensive real-world testing data on newer systems makes it challenging to fully evaluate their long-term viability and durability.

To address this challenge, manufacturers need to reassess their testing protocols and invest in more comprehensive testing methodologies that better simulate real-world conditions. This might involve conducting field tests or simulations that account for variables such as weather, structural stresses, and long-term wear and tear.

Nico Martinez, senior product manager at Unirac, emphasized a few findings from comparative testing with competitors, particularly concerning direct-to-deck attachments. These findings highlight two fundamental issues with the tests that some of the competitors are conducting:

Unirac’s internal testing has revealed challenges in meeting their claimed loads.
Their tests are performed in highly controlled laboratory settings.

Engineering Expertise for Protection, Satisfaction, and Trust

Solar racking manufacturers must understand that while meeting building codes is given, a stricter and more holistic engineering approach is critical for reliable solar mounting systems. Cutting corners on quality and relying solely on basic lab tests—testing in settings that do not represent an actual roof and operating tests that force a failure mode in a certain way—can backfire in the long run, leading to roof damage and even safety hazards. Such failures, if not addressed early, can severely damage the reputation of the solar industry as a whole, hindering its growth and eroding customer trust.

“Once roof failures start happening, it’s not just bad for our company—it is bad for the entire industry,” stressed Nico Martinez.

The solar industry must make a deliberate and unified effort to implement higher engineering standards. The answer is to simulate the absolute worst-case scenarios, adopt stricter internal standards, exceed building code requirements, and conduct rigorous field testing for diverse environments. Manufacturers can proactively ensure the safety, reliability, and longevity of their racking products by going above and beyond what is necessary. It is okay to be conservative if it ensures the safety of the customers. Understand that while there may be pressure to prioritize cost-efficiency or speed to market, the potential repercussions of compromised quality far outweigh any short-term gains.

Elevating Quality Benchmarks in Mounting Solutions—Unirac’s Golden Standards

Given that solar modules have a design life of 25+ years, it becomes a necessity to engineer mounting solutions that last and not only endure but outlive diverse environmental conditions.

However, generic testing methods, like a typical ASTM D7147 test configuration, will not expose the potential vulnerabilities that could arise in real-world scenarios. That is why Unirac undertook comprehensive testing to find extensive insights into roofing failure, such as:

Sheathing Separation from the Rafter: The sheathing, the layer of material directly attached to the rafters under the roof covering, can separate from the rafters themselves.
Nail Pull-Out: The force exerted on the sheathing panel can cause the nails securing it to pull out, compromising the mounting system.
Roofing Nail Failure: Similar to nail pull-out, extreme weather conditions can cause the roofing nails connecting to the rafters to pull out.
Nail Pull-Through: The heads of the nails used to secure the mounting system can pull through the sheathing, compromising the overall strength and stability.
Deformed and Deflected Sheathing: Under excessive pressure, the plywood sheathing can deform and deflect, eventually leading to failure of the entire mounting system.
Inconsistent Sheathing Quality: Standard testing often uses new sheathing purchased from hardware stores, which may not accurately reflect the variable strength properties and potential degradation of sheathing materials used in real-world installations over time.

Unirac’s Approach to Addressing Substandard Testing and Potential Issues

Great product engineering can eliminate most product defects early on, while rigorous product testing can set technical benchmarks in order to produce high-quality products that are safe to install. This sets the standard for Unirac’s approach.

Here’s how Unirac achieves this:

Proactive Solar Engineering: Unirac follows a hard engineering approach to identify and eliminate most potential flaws early on. This minimizes defects and ensures durability from the very beginning.
Rigorous Testing: Go beyond generic testing and controlled lab scenarios, simulating real-world conditions to achieve hard data on the products’ performance. This includes:
- Extensive Compatibility Testing: Testing products on various roofing membranes, from traditional asphalt shingles to metal and TPO roofing systems, ensuring compatibility across diverse roof types.
- Scenario Simulations: At Unirac, we do not shy away from pushing our products to the limit. We test extreme conditions, like high wind loads on roofs, to ensure our equipment can withstand the harshest weather.

The Benefits:

Quality, Reliability, and Durability: Unirac can confidently stand behind its products, backed by real-world testing data, offering peace of mind to both customers and installers.
Seamless Installation: The products are designed and tested for ease of installation, ensuring a smooth and efficient process for installers.
Worry-Free Operation: Unirac’s products are designed with a 25+ year lifespan in mind, allowing customers to enjoy the benefits of solar energy with minimal concern.

Commitment to Excellence—A Promise to Customers and Installers

Recent weather data shows a rise in the frequency and intensity of severe weather events, painting a rather concerning picture. These broader climate change trends will pose significant challenges for the solar industry, particularly concerning roof mounting solutions.

There is no doubt that innovation is crucial for the industry’s advancement, but it must be coupled with rigorous and comprehensive testing. Mounting solutions need to be meticulously evaluated to ensure they can withstand the evolving weather patterns brought about by climate change. Controlled laboratory testing methods will not adequately capture the real-world impact. Thus, necessitating shift from a minimum-standard approach to rigorous product development and testing.

“We are not just making solar mounts and systems; it is an ecosystem that ties in with building and construction,” asserts Ryan Estrada.

Ultimately, it is a company’s ethos that guides its approach. Compliance with standards and product development practices can vary among organizations. While some may view minimum standards as sufficient, others strive for excellence. Companies will have to acknowledge that compliance alone may not be sufficient at some point in the course of time. Solar technology still has significant growth potential, and as it grows, it will result in a steady increase in industry standards and customer expectations that go beyond mere compliance.