SolarMagic Chipset and Firmware Released to Detect Dangerous Arc Faults in Solar Cell Systems
NEC-compliant analog front-end IC and multi-band dynamic filtering firmware

June 20, 2011 – National Semiconductor Korea (CEO: Choi Chung-won) announced today the release of the SolarMagic™ Arc Detection Reference Design, a commercial chipset that detects dangerous DC arc faults in photovoltaic (PV) systems, consisting of the industry's first analog front-end integrated circuit (IC) and multi-band dynamic filtering firmware.

National exhibited the SolarMagic arc detection reference design at the Intersolar Europe Conference (Hall A1.151 Booth), held in Munich, Germany from June 8 to 10.

In modern PV systems, DC circuits can generate arcs of significant energy due to intermittent connections or insulation failures and damage. These arcs, reaching temperatures of 3,000 degrees Celsius, pose a threat to the safety of surrounding infrastructure and personnel. Due to these risks, the 2011 US National Electrical Code (NEC) 690.11 mandated that all newly installed PV systems must include arc fault circuit detection and protection systems. National's new SolarMagic arc detection reference design includes an analog front-end IC and Multi-Band Dynamic Filtering (MBDF) firmware. It also detects arc fault conditions and warns to cut off system power to eliminate the arc.

"The launch of National's SolarMagic arc detection reference design is the result of years of effort to understand and resolve PV module overvoltage issues in the solar industry, based on National's diverse portfolio of signal processing and power management products," said Patrick Quinn, General Manager of National's Solar IC business unit. "Along with the new integrated circuit, our arc detection reference design is one of many systems National is developing for the entire solar PV industry."

National's SolarMagic Arc Detection Firmware Information
Arcs in PV arrays are very difficult to detect. Electric arcs do not leave uniquely identifiable electronic traces. Furthermore, the power lines of a PV array act as highly effective antennas, causing various electromagnetic interferences around the array. In addition, inverters generate additional noise on the power lines. Therefore, a precise signal processing method is required to reliably detect the entire dangerous arc without fault alarms when the PV array is operating under safe conditions. MBDF firmware utilizes an advanced summary pattern recognition method to process arc traces without comparing them to fixed absolute shapes.