World first for transformerless inverters as SMA receives UL certification


The certification applies to SMA’s transformerless Sunny Boy 8000TL-US, Sunny Boy 9000TL-US, and Sunny Boy 10000TL-US inverters, and was granted as a result of complying with "UL Standard 1741 for PV and Battery-Powered Inverters", which includes requirements on transformerless inverters for the first time.

In a statement, the company said: "This UL certification can be seen as laying the foundation for the safe and wide-spread use of transformerless inverters in the U.S. Due to the special requirements of American standards, up until now PV plants here were almost always designed using galvanically isolating devices. In comparison, transformerless inverters are more efficient (among other benefits), which means the operators will benefit accordingly as a result of maximum energy yield. In addition, their reduced weight will make it significantly easier for installers to mount the devices."

In reality, continues the company, it is difficult for products that have not received UL certification to be successful in the U.S. market. In addition, according to Bernd Engel, senior vice president of Technology and Development, UL certification is not only in demand in the U.S., but also in Canada.

SMA concluded by saying its certified inverters, which can be adjusted from eight to 10 kW, are especially suited for use in PV plants from the medium power range to the megawatt class.