|
f
<br /> -: l'.''': 'Z' '''' ' ' ..,: • , . - a . .' _ -, ' '. '' ' :. - ' . - -- T - - , ' . , ,,.: -,:$'''''''„,-**,
<br /> T he following information contains the requirements f a roof moun system design - ..� "r
<br /> •
<br /> • x for Y wmd velocity of 136 miles er hour. This is a higtier,design ' • _ .. required P ,pressure than, is � � � d�
<br /> r • in �antral•Florida. This installation n will meet F.B.C. 2003, 'or cep' 'trill Florida. Supporting
<br /> `''`S'data rs provided and analyzed at the new design pressure of 61:5 psf for coastal regions,' ..y
<br /> 65.. . ' v :. r.-�.��
<br /> The Sealed Air FS, FW, and FP series panel have been tested by e. Aerot En i nee ri n
<br /> g l
<br /> Group of the Convair Division of Gerieral Dynamics Corporat' n in a;low v ocity wind'
<br /> tugnel a design load of 55.5 psf which equals a win d veto ' f 136 miles per hour. .
<br /> 2 2/7• 't:1.1
<br /> 55.5 = 0.00256 V. (35/30) • • , ,
<br /> •V_= 136 mph ,
<br /> 3
<br /> The framed series panels are attached directly to the roof structure (securely into rat ,
<br /> { ' ' ' ,- per installation instructions by factory retaining clips tested to retain' the panel at a loading ,
<br /> of 83.5 psf, or a wind velocity of 176.7 mph. Use the factory recommended clip � 6 , • ,
<br /> 4 I� I. A
<br /> ; arran gement with Factory supplied 1/4 20 lag screws having a minimum screws strength : d , ,, ',, :
<br /> ;
<br /> -• 'F of 45 psi, secured by 1/4" zinc plated thrust washers. PII1P r ' { it "
<br /> ° t . 4 F tf to ce ,. •
<br /> : I , '0,• ��� "�i7? ,i, _
<br /> •To calculate the uplift force of the section of panels, use the formula: . , _�i :;: � ' ,
<br /> M t , 6
<br /> ,�T '(p)x(A)x(N) ,1, . Where• .
<br /> i P = Pressure per square foot on the panel surface for the design velocity.
<br /> ' A = The width x length of the panel. .
<br /> • N = Number of panels mounted on the roof. • e
<br /> Exampie:' For the following example, the largest array of the largest collector used to
<br /> demonstrate the maximum exposure. Arrays should be limited to 11 collectors or less per ,
<br /> bank for thermal performance reasons. All charts supplied h been calculated on the �• ' `
<br /> new' maximum test pressure psf , and the anchorages ..ft§, prg ted to•reflecticFhe , ' • ,
<br /> � igher values... Thuttotal 'upif't of ai )1 panel section of 12' t9llectors "' 'at.a wind velgd` i f r C ' :
<br /> ' '136 „ j
<br /> Y e3,„•,•••".6 ' ,I
<br /> , , rt . i • '' = ' 55.5'•x 4 x 12x 11 = 29,304 lb:
<br /> 4 " t r� • , Lag bolt pull out force is calculated by the,thread strength gth of the lag, and the ability of
<br /> wood to hold the lag•in place. As the length of the lag increases the wood's ability to hold ' =
<br /> •
<br /> the lag increases until the tensile strength of the bolt is reached. Wood typically used in '
<br /> tz:‘, ,building roof structures is softwood having a specific
<br /> gravity of 0.55. The lag bolt pull ,
<br /> , out forcetmust exceed the uplift force determined above in order to keep the solar array
<br /> . (panel section) in place. The following pull out force is given for lag bolts in wood
<br /> 1 ' '
<br /> ' substrate. Forces are per inch of length imbedded in wood.
<br /> 1/4" • ` 260 lb./inch • 3/8" = 390 lb./inch
<br /> •
<br /> •
<br /> • ,.,
<br /> P
<br /> a
<br /> tit's'
<br />
|