[RE-wrenches] Fwd: Re: Aluminum Module Frame To GalvanizedUni-Strut

[Drake]

I've tested really old arrays that were done in the days before NEC 
grounding requirements.  No star washers, just nuts, bolts, lock 
washers and washers.  I've never seen significant resistance from one 
end of an array to the other.  This appears to be a solution to solve 
a problem that never existed in the first place, that caused a 
problem!  (The main cause of problems are solutions).

That being said, Weeb type clips may be a good idea for top mounting hardware.


  At 05:20 PM 7/13/2011, you wrote:
>Hi Guys;
>
>The islands have accelerated corrosion, but we will see the same 
>problems even in dry climates, it just might take decades instead of 
>years. I think galvanic corrosion of AL and CU is such a problem 
>that we should use the new products available such as the WEEB, and 
>take advantage of the clarified grounding requirements in NEC 2011.
>Basically I think the days of bare #6 CU running all over the array 
>modules and framing should be over. It was time and money consuming, 
>caused unnecessary corrosion, and looked bad, plus was it ever really safer?
>My own ground impedance testing says no. The most impedance is 
>usually found at the connection from the grounding electrode to the 
>earth itself, not at the array.
>
>Ray Walters
>
>On 7/13/2011 2:46 PM, Marv Dargatz wrote:
>>Drake,
>>
>>This is a HUGE problem.  If you want a real earful, talk to John 
>>Wiles, Bill Brooks, or Greg Ball about this.
>>
>>While you might think that the anodizing on the aluminum would 
>>prevent electrical contact to the copper, it doesn't last long with 
>>just a little vibration (usually due to wind).  Put this in a 
>>coastal environment, and things go bad in a hurry, often in less 
>>than one year.  Any island environment is especially bad.
>>
>>
>>See ya!
>>
>>Marv
>>Director of Technology and Support, North America
>>SolarEdge Technologies, Inc.
>>Tech Support Mobile:  +530.798.6770
>>Mobile: +530.392.0356
>>
>>From: 
>><mailto:re-wrenches-bounces at lists.re-wrenches.org>re-wrenches-bounces at lists.re-wrenches.org 
>>[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Drake
>>Sent: Wednesday, July 13, 2011 1:26 PM
>>To: RE-wrenches
>>Subject: [RE-wrenches] Fwd: Re: Aluminum Module Frame To Galvanized Uni-Strut
>>
>>
>>Marv,
>>
>>It is common practice to run bare copper ground wire over rails and 
>>under modules, which will touch the aluminum at various 
>>points.  How much of a problem is this going to create in the long run?
>>
>>Drake
>>
>>
>>
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Drake Chamberlin
ATHENS ELECTRIC
OH License 44810
CO license 3773
NABCEP Certified PV
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