Re: [RE-wrenches] Lighter tubing?

2021-07-26 Thread Ray 
We did a setup with the Snap N Rack rack on a roof once.  We just used 
the recommended galvanized SCH 40.  Its basically a readily available 
product.  I would be careful with other types of steel tubing: make sure 
it will fit the fittings.  We actually retrofitted a Snap N Rack to some 
existing pipe ground mount racking, and it turned out to be a slightly 
different diameter. Big pain.  2nd, make sure its galvanized, which can 
also slightly change the fit. 3rd,  if the snow load is 100 lb/ sq ft, 
your total array loading might be over 30,000 lbs.  Is saving a few 
pounds on the steel really worth considering?  Seems like your post 
bases on the roof are going to take quite a bit of engineering to 
support the snow load.


Also, final note, the Snap N Rack setup doesn't do very good with uplift 
wind loading.  It just attaches with pinch bolts, so we had our one roof 
rack get sucked off the roof in a hurricane. We drilled holes and 
through bolted on the replacement array, but I'm sure we violated the 
Snap N Rack 10 commandments by doing that.


I would consider other racks that might get the tilt with separate rows, 
and be overall lower to the roof?  Possibly a ballasted system?


Ray Walters
Remote Solar
303 505-8760

On 7/26/21 7:15 PM, Dana Orzel wrote:


Hey all!

I am proposing a [20] module, 35˚ tilt up array mounted on a flat roof 
in snow country - Central Idaho. Its in town, trees behind & off to 
the side a ways.


The SnapnRack design calls for [21] Pieces of 1 ½” x 21’ sched 40 pipe 
+/-. I am trying to understand the need for sched 40 pipe on the 
vertical components of this array. Though if the horizontal members 
could be switched over to tube too that would be a big savings on 
weight. I hope to eliminate the sched 40 for steel tube [stronger 
metal thinner wall].


Without reinventing the wheel, has anyone approached this issue & how 
did you address it?


Suggestions on beefy array systems that are lighter?

Spec.

[20] – Q-cell 340 watt modules.  5 columns of 4 modules.

Snow-Load - 100 PSF.

Tilt - 35˚ – The back & sides will be shrouded up to module on 
vertical members to prevent wind uplift.


Wind - 90 MPH/3 sec microburst [though IF, this ever happened there 
would be trees & garbage cans flying.]


Sched 40 -1 ½” pipe is 2.72#/ft.

1 7/8” steel tube is 1.25#/ft.

Maybe we all use schedule 40 pipe because that’s what we have always 
done & locally available. Isn’t that’s what called recycled ignorance? 
Looking for options. In todays world marketplace I am questioning this 
approach.


Thanks in advance.

Dana Orzel  Great Solar Works, Inc.

*C - 208.721.7003   d...@solarwork.com*

Idaho Contractor - # 028765 Idaho PV # 028374

NABCEP # 051112-136 www.greatsolarworks.com 



_"Responsible Technologies for Responsible People since 1988" ___

*P*Please consider the environment before printing this email.


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[RE-wrenches] Lighter tubing?

2021-07-26 Thread Dana Orzel 
Hey all!

 

I am proposing a [20] module, 35˚ tilt up array mounted on a flat roof in
snow country - Central Idaho. Its in town, trees behind & off to the side a
ways. 

The SnapnRack design calls for [21] Pieces of 1 ½” x 21’ sched 40 pipe
+/-. I am trying to understand the need for sched 40 pipe on the vertical
components of this array. Though if the horizontal members could be
switched over to tube too that would be a big savings on weight. I hope to
eliminate the sched 40 for steel tube [stronger metal thinner wall]. 

 

Without reinventing the wheel, has anyone approached this issue & how did
you address it?

Suggestions on beefy array systems that are lighter?

 

Spec.

[20] - Q-cell 340 watt modules.  5 columns of 4 modules.

Snow-Load - 100 PSF.

Tilt - 35˚ - The back & sides will be shrouded up to module on vertical
members to prevent wind uplift.

Wind - 90 MPH/3 sec microburst [though IF, this ever happened there would
be trees & garbage cans flying.]

 

Sched 40 -1 ½” pipe is 2.72#/ft.

1 7/8” steel tube is 1.25#/ft.

 

Maybe we all use schedule 40 pipe because that’s what we have always done
& locally available. Isn’t that’s what called recycled ignorance? Looking
for options. In todays world marketplace I am questioning this approach.

 

Thanks in advance.

 

 

 

Dana Orzel  Great Solar Works, Inc. 

C - 208.721.7003   d...@solarwork.com

Idaho Contractor - # 028765 Idaho PV # 028374

NABCEP # 051112-136   www.greatsolarworks.com
 

"Responsible Technologies for Responsible People since 1988"  

P Please consider the environment before printing this email.

 

 

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