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Are AC coupled systems with no DC loads exempted from the grounding rules
of DC coupled, battery based systems and the rules of DC grounding?
<br><br>
<br><br>
<blockquote type=cite class=cite cite="">This is from the Sunny Island
Manual:<br>
"External grounding of the negative pole of the batteries is
possible, because the batteries <br>
and the grid side are galvanically isolated within the Sunny Island.
<br>
• Dimenssion the cross‑section of the protective conductor
sufficiently. Thus you are <br>
ensuring that in the event of a fault the high currents occurring can be
discharged with <br>
an external grounding.<br>
• If groounding of the negative pole of the battery is necessary,
assemble this outside of <br>
the Sunny Island. <br>
<br>
As far as I am aware, the NEC code is kind of vague on grounding battery
banks (please correct me if I am wrong), it is more of a AHJ
requirement.<br>
<br>
There is no reference to ground (DC side) inside the SI.<br>
<br>
SMA America, LLC<br>
Steve Jefferson<br>
<i>Supervisor, Service Line<br>
</i>6020 West Oaks Blvd, Suite 300<br>
Rocklin, CA 95765 - 3714<br>
U.S.A.<br>
Tel: +1 916 625 0870<br>
Fax: +1 916 624-2445<br>
Service Line +1 877 697 6283 (Toll Free)<br>
Email: steve.jefferson@sma-america.com<br>
<a href="http://www.sma-america.com/">www.SMA-America.com</a><br>
<br>
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<br>
<b>From:</b> re-wrenches-bounces@lists.re-wrenches.org
[<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" eudora="autourl">
mailto:re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of
</b>August Goers<br>
<b>Sent:</b> Wednesday, April 10, 2013 2:13 PM<br>
<b>To:</b> RE-wrenches<br>
<b>Subject:</b> Re: [RE-wrenches] Fuse sizing in battery circuits<br>
<br>
Steve,<br>
<br>
So if we wanted to ground the negative would we literally run a ground
wire to one of the battery terminals? Is there anything in the NEC that
governs this? What are the deciding factors when deciding to ground the
negative or not?<br>
<br>
As a separate note, I've noticed that the negative battery terminals
measure 0 volts to ground on a Sunny Island setup once everything is
connected without any extra grounding added. I thought that there must be
some reference to ground happening in the Sunny Island but apparently I'm
wrong.<br>
<br>
Thanks, August<br>
<br>
<b>From:</b>
<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">
re-wrenches-bounces@lists.re-wrenches.org</a>
[<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" eudora="autourl">
mailto:re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of
</b>Steve Jefferson<br>
<b>Sent:</b> Wednesday, April 10, 2013 9:56 AM<br>
<b>To:</b> RE-wrenches<br>
<b>Subject:</b> Re: [RE-wrenches] Fuse sizing in battery circuits<br>
<br>
If the Batt negative is not bonded to ground, then yes SMA recommends
fusing both Positive and Negative.<br>
<br>
Also, the negative is not bonded to ground internally in the Sunny
Island.<br>
<br>
SMA America, LLC<br>
Steve Jefferson<br>
<i>Supervisor, Service Line<br>
</i>6020 West Oaks Blvd, Suite 300<br>
Rocklin, CA 95765 - 3714<br>
U.S.A.<br>
Tel: +1 916 625 0870<br>
Fax: +1 916 624-2445<br>
Service Line +1 877 697 6283 (Toll Free)<br>
Email:
<a href="mailto:steve.jefferson@sma-america.com">
steve.jefferson@sma-america.com</a><br>
<a href="http://www.sma-america.com/" eudora="autourl">
www.SMA-America.com</a><br>
<br>
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