<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
<p>Would it make sense just to upsize the conductor for this short
run? </p>
<div class="moz-cite-prefix">On 7/24/2026 5:47 AM, Jason Szumlanski
via RE-wrenches wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CAE438R901F9R9_b-n=K6WHU8FA6FGryODJGvGeuCJhxo_bPMUg@mail.gmail.com">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div dir="ltr">
<div>My read: EG4 likely omitted 15A and 20A because these are <span
class="gmail_default"
style="font-family:arial,helvetica,sans-serif"></span>c<span
class="gmail_default"
style="font-family:arial,helvetica,sans-serif">ontemplated</span> as
high-current smart load or AC-coupled inverter ports, not
branch circuit protection for small loads. The GridBOSS is
sized for things like EV chargers, HVAC, <span
class="gmail_default"
style="font-family:arial,helvetica,sans-serif"></span>w<span
class="gmail_default"
style="font-family:arial,helvetica,sans-serif">ater heaters
\u2013</span> not standard household <span class="gmail_default"
style="font-family:arial,helvetica,sans-serif"></span>r<span
class="gmail_default"
style="font-family:arial,helvetica,sans-serif">eceptables
and lighting. They expect those to be regular backup loads</span>.<span
class="gmail_default"
style="font-family:arial,helvetica,sans-serif"> The biggest
example I have to support the need to shed a 20A load is a
pool pump.</span></div>
<div><span class="gmail_default"
style="font-family:arial,helvetica,sans-serif"><br>
</span></div>
<div><span class="gmail_default"
style="font-family:arial,helvetica,sans-serif">Anyway, when
I use a GridBOSS for an off-grid installation, I almost
always use Port 4 for a 15A multiwire branch circuit to
support a convenience outlet and lighting for the area on
one leg and a generator battery charging circuit on the
other leg. I see no issue with it.</span></div>
<div><span class="gmail_default"
style="font-family:arial,helvetica,sans-serif"><br>
</span></div>
<div><span class="gmail_default"
style="font-family:arial,helvetica,sans-serif">One thing
that supports my theory that the breaker ratings are the
maximum supported per port <span class="Asgive ng"
style="border-style:none;background:none">is that the
ratings in the table overlap.</span> Looking at the table,
<span class="Asgive ng"
style="border-style:none;background:none">on line 1, port
1 supports 90-125A breakers, then the table goes on to
support 30-80A breakers for port</span> 1. The whole <span
class="Q6ibn ng" style="border-style:none;background:none">tables</span>
is a confusing mess. And what about 35A breakers? 45A?
These are common for some mini-split units. They are not in
the table, but surely would not be a problem.</span></div>
<div><span class="gmail_default"
style="font-family:arial,helvetica,sans-serif"><br>
</span></div>
<div><span class="gmail_default"
style="font-family:arial,helvetica,sans-serif">EG4 needs to
revamp this table for clarity.</span></div>
<div><span class="gmail_default"
style="font-family:arial,helvetica,sans-serif"><br>
</span></div>
<div>
<div class="gmail_default"
style="font-family:arial,helvetica,sans-serif">P.S. I have
started using Port 1 as the main load port for smaller
off-grid jobs without even using the 200A backup load port.
I just set port 1 to operate 24 hours a day. This way, you
don't need additional overcurrent protection from an
external main breaker. The downside is that the manual
bypass becomes non-functional, but otherwise it has worked
out well for me.</div>
<br>
</div>
<div>
<div dir="ltr" class="gmail_signature"
data-smartmail="gmail_signature">
<div dir="ltr">
<div><br>
Jason Szumlanski<br>
Principal Solar Designer | Florida Solar Design Group<br>
NABCEP Certified Solar Professional (PVIP)<br>
Florida State Certified Solar Contractor CVC56956<br>
Florida Certified Electrical Contractor EC13013208<br>
</div>
<div><br>
</div>
<div><br>
</div>
</div>
</div>
</div>
<br>
</div>
<br>
<div class="gmail_quote gmail_quote_container">
<div dir="ltr" class="gmail_attr">On Thu, Jul 23, 2026 at
9:24\u202fPM Dave Tedeyan via RE-wrenches <<a
href="mailto:re-wrenches@lists.re-wrenches.org"
moz-do-not-send="true" class="moz-txt-link-freetext">re-wrenches@lists.re-wrenches.org</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote"
style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="ltr">
<div>Hi All, </div>
<div><br>
</div>
<div>I will soon be installing one of these in a detached
shed, where it would be useful to have a light installed.
There will be no panel in there other than the GridBOSS,
inverters and batteries. The manual says that the smallest
breaker size that is supported is a 30a breaker. See table
below.</div>
<div><br>
</div>
<div>I emailed their tech support to ask if there would be a
problem with a 20a breaker. They gave a very basic answer
pointing me back to this same table, and then recommended
to add a subpanel, and then run a 20A circuit from there.
That seems a bit overkill for a light. I cannot see why if
a 30A breaker is allowed, a 20A breaker would not be
allowed. It is just a simple Eaton breaker. Am I missing
something here?</div>
<div><br>
</div>
<div>Cheers, </div>
<div>Dave</div>
<div><br>
</div>
<div><img
src="cid:part1.ddse2E0I.l8DtEFgJ@entech-engineering.com"
alt="image (4).png" width="542" height="135" class=""><br>
</div>
<div><br>
</div>
<span class="gmail_signature_prefix">-- </span><br>
<div dir="ltr" class="gmail_signature">
<div dir="ltr"><br style="color:rgb(34,34,34)">
<div dir="ltr" style="color:rgb(34,34,34)">
<div dir="ltr">
<div dir="ltr">
<table cellpadding="0" cellspacing="0"
style="border-spacing:0px;border-collapse:collapse;color:rgb(68,68,68);width:525px;font-size:11pt;font-family:Arial,sans-serif">
<tbody>
<tr>
<td width="125" valign="top" rowspan="6"
style="padding:0px 10px 0px 0px;font-size:10pt;border-right:1px solid rgb(236,189,0);width:125px;vertical-align:top"><img
width="96" height="95"
src="https://ci3.googleusercontent.com/mail-sig/AIorK4w9B8ItkbLOVj_3kXSEToNSG4GqEc1qAkl0q-KvGLgH-Zo8UhpcOQ_YebOrq3ZUuLGNqPigeSx2_7i8"
moz-do-not-send="true"><br>
</td>
<td style="padding:0px 0px 0px 10px">
<table cellpadding="0" cellspacing="0"
style="border-spacing:0px;border-collapse:collapse;background-color:transparent">
<tbody>
<tr>
<td valign="top"
style="padding:0px 0px 5px 10px;width:400px;vertical-align:top"><span
style="color:rgb(236,189,0);font-size:11pt;font-weight:700">Dave
Tedeyan, P.E.<br>
</span><span
style="font-size:11pt;font-weight:700"><font color="#ecbd00">Owner |
Sungineer Solar</font><br>
</span></td>
</tr>
<tr>
<td valign="top"
style="padding:5px 0px 5px 10px;font-size:10pt;vertical-align:top;line-height:17px"><span
style="color:rgb(236,189,0)"><span
style="font-weight:700">p: </span></span><span
style="font-size:10pt;color:rgb(0,0,0)">he | him | his</span><span
style="color:rgb(236,189,0)"><span
style="font-weight:700"><br>
a: </span></span><span
style="font-size:10pt;color:rgb(0,0,0)">1653 Slaterville Rd.</span> <span
style="font-size:10pt;color:rgb(0,0,0)">| Ithaca, NY 14850</span><br>
<span style="color:rgb(236,189,0)"><span
style="font-weight:700">w:</span></span><a
href="http://www.sungineersolar.com/" rel="noopener"
style="color:rgb(51,122,183);background-color:transparent"
target="_blank"
moz-do-not-send="true"><span
style="font-size:10pt;color:rgb(0,0,0)"> www.sungineersolar.com</span></a><br>
<span style="color:rgb(236,189,0)"><span
style="font-weight:700">c:</span></span><span
style="font-size:10pt;color:rgb(0,0,0)"> (607) 270-0370</span></td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</div>
</div>
</div>
</div>
</div>
</div>
_______________________________________________<br>
List sponsored by Redwood Alliance<br>
<br>
Pay optional member dues here: <a
href="http://re-wrenches.org" rel="noreferrer"
target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">http://re-wrenches.org</a><br>
<br>
List Address: <a
href="mailto:RE-wrenches@lists.re-wrenches.org"
target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">RE-wrenches@lists.re-wrenches.org</a><br>
<br>
Change listserver email address & settings:<br>
<a
href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org"
rel="noreferrer" target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><br>
<br>
There are two list archives for searching. When one doesn't
work, try the other:<br>
<a
href="https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/"
rel="noreferrer" target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/</a><br>
<a
href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org"
rel="noreferrer" target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a><br>
<br>
List rules & etiquette:<br>
<a href="http://www.re-wrenches.org/etiquette.htm"
rel="noreferrer" target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">http://www.re-wrenches.org/etiquette.htm</a><br>
<br>
Check out or update participant bios:<br>
<a href="http://www.members.re-wrenches.org" rel="noreferrer"
target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">http://www.members.re-wrenches.org</a><br>
<br>
</blockquote>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<pre wrap="" class="moz-quote-pre">_______________________________________________
List sponsored by Redwood Alliance
Pay optional member dues here: <a class="moz-txt-link-freetext" href="http://re-wrenches.org">http://re-wrenches.org</a>
List Address: <a class="moz-txt-link-abbreviated" href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a>
Change listserver email address & settings:
<a class="moz-txt-link-freetext" href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>
There are two list archives for searching. When one doesn't work, try the other:
<a class="moz-txt-link-freetext" href="https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/">https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/</a>
<a class="moz-txt-link-freetext" href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a>
List rules & etiquette:
<a class="moz-txt-link-freetext" href="http://www.re-wrenches.org/etiquette.htm">http://www.re-wrenches.org/etiquette.htm</a>
Check out or update participant bios:
<a class="moz-txt-link-freetext" href="http://www.members.re-wrenches.org">http://www.members.re-wrenches.org</a>
</pre>
</blockquote>
<pre class="moz-signature" cols="72">--
Christopher Warfel, PE
ENTECH Engineering, Inc.
PO Box 871, Block Island, RI 02807
(401) 447-5773</pre>
</body>
</html>