How the New PV-JB/MF Open Format Junction Box for PV Modules Came to Light
Multi-Contact USA Posted 09/23/2013Multi-Contact AG, a global electrical connector manufacturer using advanced contact technology, has been active in the solar industry for decades. The company is a pioneer in photovoltaics, having developed the MC3 connector system (the world’s first plug-and-play) as well as the ubiquitous MC4 connector system. Though known mainly for its PV connector products, Multi-Contact has been developing PV module junction boxes for just as long.
During the 2000s, flush with fortunes gained during the tech boom with its large semiconductor industry, American tech centers began to shift their focus to renewable energy, primarily photovoltaic technology. Regions such as Silicon Valley morphed into “Solar Valley” as a rush of new investments fueled numerous green tech startups. This created significant opportunities for the connector and junction box business, and thin-film technology became a hot commodity. Multi-Contact USA, the North American headquarters of Multi-Contact AG, responded to the market by engineering innovative custom junction box solutions for thin-film modules.
The solar industry took another turn as it entered the following decade. The global PV over-supply crisis hit the thin film market especially hard, and early 2011 through 2012 saw the demise of several thin film product manufacturers, both large and small. Concurrently a price drop in silicon gave the crystalline PV module market a boost with lower cost-per-watt ratios, especially for large, utility-scale installations. Other developments have unfolded since. Large-scale installations now require increased ampacity. New safety requirements are emerging, creating a need for module-integrated electronics for remote monitoring and shut-off.
From Multi-Contact’s perspective, these new developments within the crystalline market called for a new way of thinking about junction boxes for PV.Brian Mills, Product Manager-Photovoltaics at Multi-Contact USA, asked the question: “How do we approach the next generation of custom junction boxes for the crystalline market that keeps up with industry trends, allows for easy augmentation to address customer requirements, while remaining cost effective and quick to market?” To meet all of the industry’s needs, the junction box would have to be flexible in design, allow easy integration of new smart technologies, and meet tougher technical requirements without pricing itself out of the market.
Multi-Contact’s engineers took a collaborative approach, tapping into the technical insights of hands-on manufacturing personnel. Their solution was the PV-JB/MF Multi-Function junction box, a modular, open format junction box, designed for manual or automated assembly. The PV-JB/MF (rated 12A, 1000V) with integrated connectors allows for numerous configuration possibilities due to its open format. The base enclosure will be UL recognized, CSA certified and TÜV certified, minimizing the need for extensive retesting of customized versions of the product. With a spacious enclosure volume, it allows for several ways to accommodate the industry-standard 4 bus ribbon/3 diode configuration. It also gives PV module and smart technology device manufacturers free reign to create their own highly customized solutions by integrating their own technologies without detracting from performance or reliability. It can be supplied as a stand-alone enclosure, ready for customer-developed technologies, or as a complete solution designed and tested by Multi-Contact.
By using a cable-free, automation-friendly design, the PV-JB/MF can be manufactured cost effectively, ensuring competitive pricing without any degradation of quality. Product development and lead time are cut in half from the typical two-year timeframe to just six months, allowing faster turnaround of custom design changes as well as in-house manufacturing and testing. Leaving the cable selection and harness configurations to the system designers and installers results in both overall system cost reduction and performance benefitsby eliminating unnecessary cable expenses and product certifications. Multi-Contact and its network of manufacturing partners and cable harness customers can support cable assembly needs virtually anywhere in the world.
Making It in America: Onshoring Production
Multi-Contact’s new junction box design had arrived. When it came time to build it, the company decided that no one would be better qualified to do so than its own people – those who knew the product they had helped to develop inside and out. So, rather than outsourcing, the company invested in optimizing its California facility and enlisted homegrown talent to create and staff a new assembly line for the PV-JB/MF junction box.
Everything was conceptualized and developed in-house. To make the work as efficient as possible, the multidisciplinary team applied lean manufacturing techniques such as kaizen and poka yoke, which emphasize continuous improvement, error-proofing and minimizing waste. The manufacturing engineers built their own tuning mechanisms, welding fixtures and control fixtures for a variety of testing applications, which would allow them to personally fine-tune the product’s design and manufacture as they went along. Some manufacturing tables and equipment encasings were also developed in-house.
The “onshoring” trend has been gaining traction in the past few years, and according to Multi-Contact, it’s with good reason. “We see a number of advantages to handling the manufacturing in-house,” said Operations Manager Ian Weatherley. “With all of the work being done on-site, rather than somewhere halfway across the world, we have total control over testing and quality.” More and more U.S. companies are discovering that when their products are made in America, the “secret sauce” of pride and ownership dramatically enhances quality. Plus time-to-market is much shorter, since the product is made literally steps from where it was developed.
Taking PV-JB/MF production from start to finish, the state-of-the-art new assembly line consists of a finely coordinated chain of workstations for pin, housing, ribbon and diode assembly as well as welding, finished good tests, camera inspections, laser engraving, packaging and shipping. Each step in the process incorporates careful monitoring, control and troubleshooting. A process for gathering data is also built in, so the team can evaluate its hits and misses for implementing future process improvements.
The PV-JB/MF Multi-Function junction box was introduced at Intersolar North America in July 2013. For more information on the PV-JB/MF and Multi-Contact’s complete line of solar solutions, contact Multi-Contact USA at firstname.lastname@example.org or visit their homepage.