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Steve,<br>
<br>
A PV system GFDI integrated into the charge controller certainly
simplifies charge controller installations. Unfortunately every
charge controller that has done that has failed to correct a serious
flaw in the operation of the GFDI: under a ground fault
circumstance, the energized PV negative wire (and all those wires
that are still connected to it) remains a serious safety hazard. I
can tolerate that hazard in the PV system wiring; the PV modules are
energized by sunlight so there will be energized wires. But
energized wiring running past the GFDI should not be tolerated. NEC
690.5(C) requires a label that is visible from the batteries warning
that, if a ground fault is indicate, normally grounded wires may be
energized. That's a good warning for someone that might be doing
maintenance on the batteries. Trouble is the dc wiring to the
inverters, lights, refrigerator, or anything else may also be
energized. It's a dangerous circumstance that isn't necessary and
shouldn't be allowed. If the external GDFI device were to simply
open both PV+ and PV- conductors, there would be no hazard except
between the GFDI and the PV array. The NEC, as now written, even
allows both conductors to be opened. It's an easy fix, at least with
the external GFDI it is an easy fix, to a design flaw that has the
potential to kill someone. Outback shouldn't simply put a GFDI in
the charge controller, they should design one that is safe too.<br>
<br>
It is safe to return to the list now. The rant is over.<br>
<pre class="moz-signature" cols="72">Kent Osterberg
Blue Mountain Solar, Inc.
<a class="moz-txt-link-abbreviated" href="http://www.bluemountainsolar.com">www.bluemountainsolar.com</a>
</pre>
<br>
On 5/23/2012 12:18 PM, Steve Higgins wrote:
<blockquote
cite="mid:8AD915B7D0FD164A800605B95BC387030C4A4080@mbx024-w1-ca-1.exch024.domain.local"
type="cite">
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<div dir="ltr" align="left"><span class="434411319-23052012"><font
color="#0000ff" face="Arial" size="2"> </font></span></div>
<div dir="ltr" align="left"><span class="434411319-23052012"><font
color="#0000ff" face="Arial" size="2">From what I
understand, future controllers from Outback Power will
incorporate the Ground Fault detection into the controller.
</font></span></div>
<div dir="ltr" align="left"><span class="434411319-23052012"></span> </div>
<div dir="ltr" align="left"><span class="434411319-23052012"></span> </div>
<div align="left"><font face="Arial" size="2">
<div align="left"><font face="Arial" size="2">Steve Higgins</font></div>
<div align="left"><font face="Arial" size="2">Sales
Application Engineering Mgr</font></div>
<div align="left"><font face="Arial" size="2">Direct
360-618-4313</font></div>
<div align="left"><font face="Arial" size="2">Outback Power
Technologies </font></div>
<div align="left"><font face="Arial" size="2">5917 195th
Street N<span class="727134612-11072011">E</span>
Arlington, Washington 98223</font></div>
<div align="left"> </div>
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<hr tabindex="-1">
<font face="Tahoma" size="2"><b>From:</b>
<a class="moz-txt-link-abbreviated" href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a>
[<a class="moz-txt-link-freetext" href="mailto:re-wrenches-bounces@lists.re-wrenches.org">mailto:re-wrenches-bounces@lists.re-wrenches.org</a>]
<b>On Behalf Of </b>William Miller<br>
<b>Sent:</b> Wednesday, May 23, 2012 11:22 AM<br>
<b>To:</b> RE-wrenches<br>
<b>Subject:</b> Re: [RE-wrenches] Finding ground faults<br>
</font><br>
</div>
Steve:<br>
<br>
IMHO, a brilliant suggestion.<br>
<br>
William Miller<br>
<br>
<br>
At 11:19 AM 5/23/2012, you wrote:<br>
<blockquote class="cite" cite="" type="cite">Steve,<br>
<br>
It would be appropriate for the GFDI to have 80-amp rated
contacts that do not have an over-current trip mechanism. IMHO,
the fact that they can trip on over-current and unnecessarily
interrupt the dc system bond is a serious design flaw.<br>
<br>
<pre>Kent Osterberg
Blue Mountain Solar, Inc.
<a moz-do-not-send="true" href="http://www.bluemountainsolar.com">www.bluemountainsolar.com</a>
</pre>
</blockquote>
<br>
<br>
</blockquote>
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