Arc flash safety concerns for solar panels

The proliferation of solar panels used in industrial and commercial building is a reflection of the decreasing cost of the photovoltaic modules and the increasing interest in renewable energy sources. The wide spread use of photovoltaic systems increases the risk of exposure to safety hazards that are inherently associated to nonlinear power sources. It is a well-known fact that the standard protection devices are inefficient in detecting short circuit faults in photovoltaic systems. In addition, it is now recognized that the maximum incident energy deployed by a DC arc flash in a photovoltaic system is higher, and in many instances significantly higher, than those estimated by using the guidelines given by the NFPA 70E and the CSA Z462-12 standards. Use of the existing guidelines can result in personnel being exposed to much higher safety risks than previously thought. These safety hazards are described in this paper.