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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Kingsley,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>The concern I have about this unit, and many other inexpensive
ones like it, is that it does not have enough resolution in the low impedance
area. PV arrays can have an impedance to ground of as low as 2kOhms. A
resolution of 0.1MOhms will likely not cut it. I just bought a $175 meter for
fun and I will take it out into the field to try it next to the Fluke 1520. If
we can get decent information, great. But the better resolution may require
spending closer to the $700 or more. <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>The key is that you don’t want to be chasing a ground fault that
really does not exist. The resistance to ground can be so low that a simple
meter will call it ground-faulted. I’ll let you know what I find out. I’m
betting that megger testing PV arrays is about to get required much more
regularly.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Bill.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
re-wrenches-bounces@lists.re-wrenches.org
[mailto:re-wrenches-bounces@lists.re-wrenches.org] <b>On Behalf Of </b>Kingsley<br>
<b>Sent:</b> Saturday, April 11, 2009 9:24 PM<br>
<b>To:</b> RE-wrenches<br>
<b>Subject:</b> Re: [RE-wrenches] Megger Testers<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
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