wdl124

http://www.ul.com/global/documents/offerings/industries/buildingmaterials/fireservice/PV-FF_SafetyFinalReport.pdf

Have done a number of installs on the electric side. There is always a DC and AC disconnect installed some where. DC is sometimes in the inverter and only disconnects the feeds from the panels from the inverter. Depending on system the panels and wires from them may remain energized (even at night due to flood lighting). AC disconnect should by near the existing service disconnect or outside meter. Some systems will deenergize the roof panels when power is removed but not always. DC panels have up 500 Volts. Cutting thru them is not a good idea! Conuit and wire on interior of attic is required to be 10" from roof surface so you dont get hit when cutting open. Disconnect information is suppose posted at meter and service mains. As for clearence working on roof, NYC has some consideration for fire fighting but have not run it to any outside of NYC.