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<p class=MsoNormal><em><i><font size=3 color="#555555" face=Arial><span
style='font-size:12.0pt;font-family:Arial;color:#555555'>Hi There,<o:p></o:p></span></font></i></em></p>
<p class=MsoNormal><em><i><font size=3 color="#555555" face=Arial><span
style='font-size:12.0pt;font-family:Arial;color:#555555'><o:p> </o:p></span></font></i></em></p>
<p class=MsoNormal><em><i><font size=3 color="#555555" face=Arial><span
style='font-size:12.0pt;font-family:Arial;color:#555555'>This from the Wiley
website is an interesting summary…<o:p></o:p></span></font></i></em></p>
<p class=MsoNormal><em><i><font size=3 color="#555555" face=Arial><span
style='font-size:12.0pt;font-family:Arial;color:#555555'><o:p> </o:p></span></font></i></em></p>
<p class=MsoNormal><em><i><font size=3 color="#555555" face=Arial><span
style='font-size:12.0pt;font-family:Arial;color:#555555'>I am assuming that
this is an up to date comment.<o:p></o:p></span></font></i></em></p>
<p class=MsoNormal><em><i><font size=3 color="#555555" face=Arial><span
style='font-size:12.0pt;font-family:Arial;color:#555555'><o:p> </o:p></span></font></i></em></p>
<p class=MsoNormal><em><i><font size=3 color="#555555" face=Arial><span
style='font-size:12.0pt;font-family:Arial;color:#555555'>========================================================<o:p></o:p></span></font></i></em></p>
<p class=MsoNormal><em><i><font size=3 color="#555555" face=Arial><span
style='font-size:12.0pt;font-family:Arial;color:#555555'><o:p> </o:p></span></font></i></em></p>
<p class=MsoNormal><em><i><font size=3 color="#555555" face=Arial><span
style='font-size:12.0pt;font-family:Arial;color:#555555'>Brian Teitelbaum (AEE
Solar Tech Rep) has authored the following guide to one of the most debated
topics in the industry. I am sure you will find this explanation of module
grounding helpful.</span></font></i></em><font color="#555555" face=Arial><span
style='font-family:Arial;color:#555555'><o:p></o:p></span></font></p>
<p><strong><b><u><font size=3 color="#555555" face=Arial><span
style='font-size:12.0pt;font-family:Arial;color:#555555'>Tech note from Brian
Teitelbaum:</span></font></u></b></strong><font color="#555555" face=Arial><span
style='font-family:Arial;color:#555555'><o:p></o:p></span></font></p>
<p><font size=3 color="#555555" face=Arial><span style='font-size:12.0pt;
font-family:Arial;color:#555555'><img width=93 height=102 id="_x0000_i1027"
src="cid:image003.jpg@01CB53E6.7827F860" alt=lay-in-lug
class="alignleft size-full wp-image-310" title=lay-in-lug>Lay-In lugs are sold
in ten packs (part number 051-03414), with the special
“thread-forming” screw. That #10-32 “thread-forming
screw” that comes with the lugs in the ten-packs, is a very special
screw, and is very hard to find out there in the world. We had to contract with
a screw manufacturer to get them. They are different than a
“thread-cutting” screw, or a “ self-tapping” screw.
Both of those type of screws actually cut out some of the metal from the module
frame as they “cut” the threads. This creates a microscopically
loose thread connection that can allow oxygen in and create corrosion over
time. They are not usable for a permanent ground connection. The “thread-forming”
screw actually “folds” the metal, and “forms” a thread
in such a way that there is an oxygen-free junction between the frame metal and
the screw. This produces a better electrical “bond” and a proper
ground connection that will last over time.<o:p></o:p></span></font></p>
<p><font size=3 color="#555555" face=Arial><span style='font-size:12.0pt;
font-family:Arial;color:#555555'>This is what the module manufacturers have in
the past specified, which is why we have sold tens of thousands of them over
the years.<o:p></o:p></span></font></p>
<p><font size=3 color="#555555" face=Arial><span style='font-size:12.0pt;
font-family:Arial;color:#555555'>However… New thinking (mostly from John
Wiles who helps to write the solar section of the Code, and is a stickler for
detail) has suggested that the #10-32 thread-forming screw does not grab enough
metal in the module frame to make a proper ground. Module frames are made from
rather thin aluminum, and even though the 32-thread-per-inch screw has very
fine threading, the module frames are only thick enough for the screw to make
contact with only about two of the screw’s threads. Not a whole lot of
contact area. Wiley Electronics, who make the WEEB equipment, has demonstrated
with actual tests that the screw gets very hot and the connection fails when
carrying high current (amps) in a simulated fault condition.<o:p></o:p></span></font></p>
<p><font size=3 color="#555555" face=Arial><span style='font-size:12.0pt;
font-family:Arial;color:#555555'>John Wiles now recommends that the lug be
connected to the module frame with stainless steel bolts and nuts, with flat
washers and a lock washer that makes much better contact with the frame. But
since frames are anodized, and the anodizing actually acts as an insulator
preventing a good electrical connection (hence the need for the thread-forming
screw to fold the metal, breaking the anodizing, and creating an oxygen-free
connection to prevent the aluminum from re-oxidizing, which is essentially
re-anodizing), Wiles says that you have to take some Emory Cloth (sandpaper)
and scrape off the anodizing where the lug contacts the frame. Then to prevent
oxidation, the scraped area has to be covered with a (messy) anti-oxidant
paste, and the lug bolted down onto that. Messy, time consuming, ugly, and very
hard to do with any consistency. And it may even violate the module warranty.<o:p></o:p></span></font></p>
<p><font size=3 color="#555555" face=Arial><span style='font-size:12.0pt;
font-family:Arial;color:#555555'>I think that using a stainless star washer
between the lug and the frame, would be better, even though Wiles has not given
his blessing to that idea. The star washer bites into the aluminum with a
greater amount of contact than just a couple of screw threads, and is much
quicker and more consistent than sandpaper and paste. We may swap the
thread-forming screw out for the bolted hardware in the future (so much to
do….so much to do…)<o:p></o:p></span></font></p>
<p><font size=3 color="#555555" face=Arial><span style='font-size:12.0pt;
font-family:Arial;color:#555555'><a href="http://www.we-llc.com/WEEB.html"><span
style='text-decoration:none'><img border=0 width=123 height=123
id="_x0000_i1028" src="cid:image004.jpg@01CB53E6.7827F860" style='border-width:
initial;border-color:initial;border-bottom-style:none;border-left-style:none;
border-right-style:none;border-top-style:none;margin-bottom:0px;margin-left:
0px;margin-right:0px;margin-top:0px;padding-bottom:0px;padding-left:0px;
padding-right:0px;padding-top:0px' alt=wiley-clip
class="alignleft size-full
wp-image-307" title=wiley-clip></span></a>In my
opinion, the WEEB-6.7 lug is far superior to either method above. It is a wider
lug, which has much more surface area in contact with the module frame (or
mounting rail where it is more commonly attached), which spreads out the heat
developed during a ground short. The stainless steel WEEB washer that comes
with the lug has 4 “ nubs” that bite into the module or rail metal,
and crushes to form an oxygen-free connection. It is ETL Listed to UL 467
grounding standards (as is our lay-in lug, which is UL Listed directly by UL).
The solar module manufacturers are (slowly) changing their installation
instructions to allow them. Evergreen, REC, Mitsubishi, Sharp, Kyocera,
Unisolar, and Suntech approve WEEBs and Wiley has their documentation on their<span
class=apple-converted-space> </span><a
href="http://www.we-llc.com/WEEB.html"><font face="Times New Roman"><span
style='font-family:"Times New Roman"'>website</span></font></a>. SunPower at
this time does<span class=apple-converted-space> </span><u>not</u><span
class=apple-converted-space> </span>approve them, but Wiley is working
with SunPower to remedy that.<o:p></o:p></span></font></p>
<p><font size=3 color="#555555" face=Arial><span style='font-size:12.0pt;
font-family:Arial;color:#555555'>However… Only the latest edition of the
National Electrical Code (NEC-2008) has wording that approves of WEEB
equipment, but there are many areas of the country that have not yet adopted
the 08 Code. Because of this, many electrical inspectors are not allowing
WEEBs. Oregon and Colorado seem to be particular problem areas, but all dealers
should discuss WEEB equipment with their local inspector to determine if they
will be approved. I think that this is just a temporary problem, but a problem
none-the-less.<o:p></o:p></span></font></p>
<p><font size=3 color="#555555" face=Arial><span style='font-size:12.0pt;
font-family:Arial;color:#555555'>Additional WEEB note: With the SnapNrack, use
the WEEB PMC washers to ground the modules to the rails. The WEEB lugs, and
WEEB splices can be attached to the SnapNrack rails by drilling a hole in the
side of the rail for the WEEB bolt to go through. Wiley Electronics is working
on making custom parts for the SnapNrack, which should be available soon.<o:p></o:p></span></font></p>
<p><font size=3 color="#555555" face=Arial><span style='font-size:12.0pt;
font-family:Arial;color:#555555'>Additional additional WEEB note: The WEEB
washers can only be used with the SolarMount Top-Mount clamps, not the
Back-Mount clips, and not with SunFrame. With back-mount clips, and SunFrame,
use one WEEB lug (or our lay-in lug) on each module, and one lug per frame
rail.<o:p></o:p></span></font></p>
<p><font size=3 color="#555555" face=Arial><span style='font-size:12.0pt;
font-family:Arial;color:#555555'>==================================================
T<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 color=blue face=Arial><span style='font-size:
12.0pt;font-family:Arial;color:blue'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><font size=3 color=blue face=Arial><span style='font-size:
12.0pt;font-family:Arial;color:blue'><o:p> </o:p></span></font></p>
<div>
<p class=MsoNormal><font size=3 color=blue face=Arial><span lang=EN-NZ
style='font-size:12.0pt;font-family:Arial;color:blue'>Carl Emerson<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 color=blue face=Arial><span lang=EN-NZ
style='font-size:12.0pt;font-family:Arial;color:blue'>Free Power Co.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 color=blue face=Arial><span lang=EN-NZ
style='font-size:12.0pt;font-family:Arial;color:blue'>Land line +64 9 473 4286</span></font><font
color=blue><span lang=EN-NZ style='color:blue'><o:p></o:p></span></font></p>
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style='font-size:12.0pt;font-family:Arial;color:blue'>Mobile +64 22 630 9689</span></font><font
color=blue><span lang=EN-NZ style='color:blue'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 color=blue face=Arial><span lang=EN-NZ
style='font-size:12.0pt;font-family:Arial;color:blue'>Email
emerson@freepower.co.nz<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 color=blue face=Arial><span lang=EN-NZ
style='font-size:12.0pt;font-family:Arial;color:blue'>Web
www.freepower.co.nz<o:p></o:p></span></font></p>
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