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<DIV><FONT face=Arial>Wrenches</FONT></DIV>
<DIV><FONT face=Arial>Over the years I have heard almost nothing about soldering
of electrical connections in PV circuits, AC or DC. The only reference I recall
is from the recommendation that one should crimp AND solder larger compression
fittings to assure a permanent connection. There were references to
factory made battery cable crimps not holding after installation
and during the final "pull-test". </FONT></DIV>
<DIV><FONT face=Arial>I can't find any reference to the practice in the NEC,
either pro or con. It seems that any technique so susceptible to poor results
would be at least addressed. </FONT></DIV>
<DIV><FONT face=Arial>The reason I want to definitively address this
practice, by the Wrenches community, is this.</FONT></DIV>
<DIV><FONT face=Arial>A group of PV industry specialists were invited to
help develop a curriculum for a state funded technical college with 4
separate campuses. The Waco Campus, with the fuel cell and
wind degree programs, is now creating a solar
installer technician degree program. </FONT></DIV>
<DIV><FONT face=Arial>A group of experts spent two days picking our
brains to help create an overview plus detailed duties,
tasks and the separate steps involved in the design/installation
process.</FONT></DIV>
<DIV><FONT face=Arial>So now that the initial draft is finished we are
asked to critique it. </FONT><FONT face=Arial>One of the "General Knowledge"
items is <U>soldering techniques</U>. </FONT></DIV>
<DIV><FONT face=Arial>I need to mention that the degree will cover
both PV and thermal installs. Of course some soldering is necessary in the
thermal installation process, less since the introduction of compression
connections, but I'm interested in addressing the electrical side. </FONT></DIV>
<DIV><FONT face=Arial>If any negative long-term effects from solder
joints have been discovered I would like to hear about them. If they
seem serious enough, I would consider recommending that the
staff include a clarification that electrical soldering should be avoided.
</FONT><FONT face=Arial>If the long-term effect is negligible, it is still
possible to do an electrically poor job even using top quality equipment.
</FONT></DIV>
<DIV><FONT face=Arial>I'll defer to the collective knowledge of this
organization.</FONT></DIV>
<DIV><FONT face=Arial>Thanks as always</FONT></DIV>
<DIV><FONT face=Arial>Jim Duncan<BR>North Texas Renewable Energy
Inc<BR>817.917.0527<BR><A
href="mailto:ntrei@earthlink.net">ntrei@earthlink.net</A><BR><A
href="http://www.ntrei.com">www.ntrei.com</A> </FONT></DIV></BODY></HTML>