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<DIV dir=ltr align=left><SPAN class=868314517-14092010>Stir
away....</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=868314517-14092010></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=868314517-14092010>Modern locking module
connectors serve as DC disconnects for micro-inverters. This point was
alluded to in the Code Corner sidebar, but not addressed in detail.
I</SPAN><SPAN class=868314517-14092010>t takes a little dance along Route
690 to drive the point home to OCD-afflicted AHJs... But it's right
there...</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=868314517-14092010></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=868314517-14092010>The simplest dance steps
generally start with 690.14(A). This clause specifically says disconnects don't
have to be suitable as service equipment and must comply with
690.17.</SPAN><SPAN class=868314517-14092010> 690.17 requires
disconnects to be manually operable switches or breakers that meet a host of
requirements. And then there's the exception, which throws all that out the
window... Or off the roof, as the case might be. </SPAN><SPAN
class=868314517-14092010><EM>(Exception: A connector shall be permitted to be
used as an ac or a dc disonnecting means, provided that it complies with the
requirements of 690.33 and is listed and identified for the use.)</EM> Listed
and identified as a PV connector meets this requirement. </SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=868314517-14092010></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=868314517-14092010>As your AHJ is quivering
with OCD discomfort... Quickly flip to 690.33 to send him/her into full-on
convulsions... </SPAN></DIV>
<DIV> </DIV>
<DIV><SPAN class=868314517-14092010>690.33 requires connectors to be polarized,
noninterchangeable with other stuff on the premises, guarded live parts,
latching or locking, require a tool to open, 1st make/last break grounding
member and... Either be rated for interrupting current without hazard to the
operator OR require a tool to open and marked "Don't open under load".
</SPAN></DIV>
<DIV><SPAN class=868314517-14092010></SPAN> </DIV>
<DIV><SPAN class=868314517-14092010></SPAN><SPAN
class=868314517-14092010>Demonstrate your compliance to the AHJ this way: Flip
your module over, grab both connectors, plug them into each other, yank on the
wires to demonstrate that a tool is required to open the connector, and flick
the sticker-tape labels that say "Do Not Disconnect Under Load". Hand the
connection to your AHJ. Make hm or her check it out closely. While he/she is
examining the connection, reconciling in their own head the irrational
concept that a disconnect doesn't have to be a switch here.... Turn the module
to face the sun and point out to them that they are now holding an energized
dead short. Just for fun :)</SPAN></DIV>
<DIV><SPAN class=868314517-14092010></SPAN> </DIV>
<DIV><SPAN class=868314517-14092010>If they can't wrap their head around the
concept, take them over to your work truck. Pull out a skilsaw. Show them the
nameplate amps and discuss the power of the tool. Way more watts and
higher voltage than your module. Carry the thing over to a live
receptacle, plug it in, squeeze and hold the trigger, pull the plug out of the
receptacle. Happens every day with all kinds of tools and appliances.
</SPAN><SPAN class=868314517-14092010>There's no label on the cord or receptacle
to say you can't... </SPAN><SPAN class=868314517-14092010></SPAN></DIV>
<DIV><SPAN class=868314517-14092010></SPAN> </DIV>
<DIV><SPAN class=868314517-14092010>Now compare this to your module connectors
to demonstrate how much safer and more effective the locking, labeled connectors
are. Buried up there behind the modules and all. Where only a qualified person
can get to them. Where, in the event of an emergency, shutting down the ac
circuit reduces the maximum potential current to one module. No matter how
bad the fault is or where it's located. Which is the lowest possible unit of
energy in a modern PV system. Can't get much safer than that!</SPAN></DIV>
<DIV><SPAN class=868314517-14092010></SPAN> </DIV>
<DIV><SPAN class=868314517-14092010>Hope it didn't take too long to fall
asleep...</SPAN></DIV>
<DIV><SPAN class=868314517-14092010></SPAN> </DIV>
<DIV><STRONG><I><SPAN
style="FONT-FAMILY: 'Monotype Corsiva'; mso-bidi-font-family: Tahoma">Matt
Lafferty</SPAN></I></STRONG></DIV>
<DIV class=Section1>
<P class=MsoNormal><SPAN style="FONT-FAMILY: Arial; FONT-SIZE: 10pt"><A
href="mailto:gilligan06@gmail.com">gilligan06@gmail.com</A></SPAN></P></DIV>
<DIV><SPAN class=868314517-14092010> </SPAN></DIV><BR>
<DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT face=Tahoma><B>From:</B> re-wrenches-bounces@lists.re-wrenches.org
[mailto:re-wrenches-bounces@lists.re-wrenches.org] <B>On Behalf Of
</B>SOLARPRO@aol.com<BR><B>Sent:</B> Tuesday, September 14, 2010 10:19
AM<BR><B>To:</B> re-wrenches@lists.re-wrenches.org<BR><B>Subject:</B>
[RE-wrenches] DC Discos for Enphase<BR></FONT><BR></DIV>
<DIV></DIV><FONT id=role_document color=#000000 size=2>
<DIV>Howdy Wrench<SPAN class=868314517-14092010> </SPAN></DIV>
<DIV>I don't try to stir things up, but I was just wondering last night as I
fell asleep reading the latest issue of HomePower magazine (# 139), if anybody
else caught a chill when they read this in the Code Corner (highlighted in a
box):</DIV>
<DIV> </DIV>
<DIV>"Both microinverters and microinverters attached to PV<BR>modules in the
field or in the factory that have any exposed<BR>DC single conductor cables are
required to meet all of the<BR>NEC’s DC wiring requirements. These may include
Section<BR>690.5 ground-fault detector requirements, DC and AC<BR>disconnect
requirements (potentially handled by connectors<BR>listed as disconnects), and
inverter DC grounding-electrode<BR>requirements."</DIV>
<DIV>- John Wiles</DIV>
<DIV> </DIV>
<DIV> Which begs the question: Are <any> module connectors
currently listed as disconnects?</DIV>
<DIV> As well as: If DC voltages for each disconnect are less than 48
V, would a simple switch suffice, should the poor hapless installer
run into an AHJ with OCD? </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV><FONT lang=0 size=3 PTSIZE="12" FAMILY="SANSSERIF">Patrick A.
Redgate</FONT><FONT lang=0 color=#000000 size=2 PTSIZE="10"
FAMILY="SANSSERIF"><BR><B><I>AMECO Solar, Inc.<BR>Serving Solar
California<BR>Since 1974<BR>7623 Somerset, Blvd.<BR>Paramount, CA
90723<BR>562-633-4400<BR></B></I><A
href="http://www.solarexpert.com/">www.solarexpert.com</A><U><BR><A
href="http://www.amecosolar.com/">www.amecosolar.com</A><BR><BR></U></FONT></DIV></FONT></BODY></HTML>