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<font size=3>Friends:<br><br>
When installing modules on extruded rail systems, I worry that any
vibration or motion could loosen top-down clamps. Unlike bottom-up
systems that install with tried-and-true bolts and lock washers through
captive holes, clamp systems seem less "positive" in holding
capability. If one rail in the proposed design moves in relation to
the other, the clamps could loosen and the modules could eventually slide
right off the rail. It appears that wind turbulence could rock the
modules in the proposed design, there is a lot of leverage for
that. This might loosen clamps.<br><br>
I hesitate to design my own racking. Small business management is
all about controlling risk. I do not want to be responsible for
damaged modules if my design fails.<br><br>
At least one local AHJ forbids home-brew racks for a permitted
system. I'm not sure I support that restrictive approach. I
might suggest allowing them for owner-builder systems where the home
owner assumes the liability. For myself, the remaining tasks
associated with installing a system properly have enough pitfalls without
me playing structural engineer.<br><br>
And lastly, it is my understanding that Solar World had temporarily
abandoned mounting holes in the back rails of their new "Plus"
modules (my quotes) and even abandoned the flanges altogether.
According to what I heard, industry pressure forced them to add them back
in, but as an option. This is third-hand knowledge, but I do know
that removing the option to mount panels with through bolts would be a
big mistake.<br><br>
William Miller<br><br>
<br><br>
<br>
<blockquote type=cite class=cite cite>Here is my \u201ccobulated\u201d idea,
admittedly done this way to take advantage of parts in stock:<br>
<br>
<a href="http://www.fafcosolar.com/download/402/Cobulate.pdf">http://www.fafcosolar.com/download/402/Cobulate.pdf</a><br>
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