[RE-wrenches] iron & aluminum

[Ray Walters]

I've seen a couple of homemade pole mounts that were really good, but 
most are not properly designed.  Fabrication experience is good, but the 
problems I've seen were design issues, not bad welding. (this goes for 
commercial racks too)  Ground mounts are less prone to errors, but pole 
mounts are actually relatively complicated designs.  One gusset missing, 
and the whole thing could twist off the pole in a storm.
On the steel vs aluminum issue, it depends on the how wet it is.  In dry 
climates I've seen painted steel last for decades.  In Hawaii, I've seen 
painted steel completely gone in 5 years.

R.Ray Walters
CTO, Solarray, Inc
Nabcep Certified PV Installer,
Licensed Master Electrician
Solar Design Engineer
303 505-8760

On 5/28/2015 8:21 PM, RM You wrote:
> Hi Wrenches, I have had a couple of customers want to fabricate their own PV pole mounts and racks out of iron. Aside from the galvanic corrosion and weight issues is there anything else I should caution these guys about? Any stories about failures etc? My druthers are to stay with the engineered aluminum pole mounts but when you’re dealing with someone with fabrication experience and the cost for pre-fab is high then the obvious outcome occurs. If the unit is properly treated/painted I imagine it could last many years. Is there a way to attach an anode to such a rack or would simple non conductive insulation between panels and rack be the best answer?
>
> Ron Young
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