[RE-wrenches] dpw top of pole mount pipe problems

[jay peltz]

Hi Jeff,

I use them all the time and love them.

however I did see two that while didn't fail where failing.
The wind direction was due east and west.
This caused the  main pivot bolt to wear excessively and also bending  
the strongback allowing the rack to rock side to side.
The customer had to actually install heavy straps to prevent it from  
rocking.

jay

peltz power

On Feb 3, 2009, at 10:00 PM, Jeff Yago wrote:

> We have installed lots of pole mounted systems and we stay with what  
> is recommended by the racking manufacturer.
>
> I have witnessed several different top of pole solar arrays and  
> solar-powered street lights that had been installed by others that  
> were swaying 2 to 3 FEET at the top, and twisting almost 90 degrees  
> of rotation during brief very gusty winds.  Yes, these were tall  
> poles which allowed more twisting and bending than a typical 8 to 10  
> foot hight pole, but I can guarantee you if these were made of cast  
> iron they would have snapped off in minutes.
>
> Its hard to believe just how far steel can twist and bend when  
> supporting a large surface area in high winds without damage.  I say  
> you should tell your client to install a nice basketball net on his  
> pole and then you should run as fast as you can and don't look back.
>
>
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