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<FONT SIZE="4"><FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>This seems more convenient than remembering the constants for copper and aluminum. Please note that I did not give the complete units for those in my previous email. The units for “k” in those formulas is ohms/mil foot.<BR>
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On 12/8/08 6:48 PM, "Michael Gullo" <mgullo3@comcast.net> wrote:<BR>
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</SPAN></FONT></FONT><BLOCKQUOTE><FONT SIZE="4"><SPAN STYLE='font-size:11pt'><FONT FACE="Arial">Marco,<BR>
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</FONT><FONT FACE="Arial">I use the following formulas:<BR>
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</FONT><FONT FACE="Arial">single-phase Vd = (I x L x R x 2)/1000<BR>
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</FONT><FONT FACE="Arial">3-phase Vd = (1.73 x I x L x R)/1000<BR>
</FONT><FONT FACE="Calibri, Verdana, Helvetica, Arial"> <BR>
</FONT><FONT FACE="Arial">L = one-way length<BR>
R = resistance of conductor from Table 8 (usually from uncoated copper ohm/kFT column)<BR>
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</FONT><FONT FACE="Arial">Mike<BR>
Michael Gullo<BR>
Solar Solutions LLC<BR>
Marlton, NJ<BR>
NABCEP Certified PV Installer ˙<BR>
mgullo@solarsolutionsnj.com<BR>
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----- Original Message ----- <BR>
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<B>From:</B> Marco <a href="mailto:marco@pvthawaii.com"><mailto:marco@pvthawaii.com></a> <BR>
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<B>To:</B> re-wrenches@lists.re-wrenches.org <BR>
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<B>Sent:</B> Monday, December 08, 2008 5:12 PM<BR>
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<B>Subject:</B> [RE-wrenches] voltag drop<BR>
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</FONT><FONT FACE="Arial">I feel kinda foolish in asking this.....but when calculating voltage drop in a conductor over distance, do I use the one-way or round-trip distance?<BR>
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</FONT><FONT FACE="Arial">thanks,<BR>
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</FONT><FONT FACE="Arial">marco<BR>
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<IMG src="cid:3311615036_16685969" > <BR>
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</FONT></SPAN><FONT FACE="Arial"><SPAN STYLE='font-size:10pt'>Marco Mangelsdorf, Ph.D.</SPAN></FONT><FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>, </SPAN></FONT><FONT FACE="Arial"><SPAN STYLE='font-size:10pt'>President</SPAN></FONT><FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'> <BR>
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