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The following information contains the requirements for a roof-mounted system designed - for a wind velocity of 136 miles per hour. This is a higher design pressure than is required in central Florida. This installation will meet F.RC. 2003 for central Florida. Supporting data is provided and analyzed at the new design pressure of 61.5 psf for coastal regions. The Sealed Air FS, FW, and FP series panel have been tested by, e Aero Engineering Group of the Convair Division of General Dynamics Corpo . n' a low v ocity wind tunnel to a design load of 55.5 Pst: which equals a wind velo. f 136 miles hour. 2 2fT 55.5 = 0.00256 V (35/30) V= 136 mph The framed series panels are attacbed directly to the roof structure (securely into rafters) per installation instructions by factory retaining clips tested to retain the panel at a loading of83.5 pst: or a wind velocity of 176.7 mph. Use the factory recommended clip arrangement with Factory supplied 1/4 - 20 lag screws having a minimum tensile strength of 45,000 psi, secured by 114" zinc plated thrust washers. To calculate the uplift force of the section of panels, use the formula: (P) x (A) x (N) Where: P = Pressure per square foot on the panel surface for the design velocity. A = The width x length of the panel. N = Nmnber of panels mounted on the roof. Example: For the following example, the largest array of the largest collector is used to demonstrate the maximum exposure. Arrays should be limited to 11 collectors or less per bank for thermal performance reasons. All charts supplied have been calculated on the new maximum test pressme of 61.5 pst:, and the anchorages are prorated to reflect the higher values. The total uplift of an 11 panel section of 12' conectors at a wind velocity of 136 mph will be: 55.5 x4x 12 xII =29,304 lb. Lag bolt pull out force is calculated by the thread strength of the lag, and the ability of woodto hold the lag in place. As the length of the lag increases the wood's ability to hold the lag increases until the tensile strength of the bolt is reached. Wood typically used in ~uilding roof structures is softwood having a specific gravity of 0.55. The lag bolt pull out force must exceed the uplift force determined above in order to keep the solar array (panel section) in place. The following pull out force is given for lag bolts in wood substrate. Forces are per inch oflength imbedded in wood. 1/4" = 260 lb./inch 3/8" = 390 lb.rmch