<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#ffffff" text="#000000">
Jay,<br>
When we faced this issue recently, we used it as an opportunity to
upgrade to a 48V system. The obsolescence and lack of Schneider
support for the SW4024 contributed to the logic of this approach.<br>
<br>
At 48V an MX60 will handle 3200 watts.<br>
<br>
<div class="moz-signature">
<style>p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: "Times New Roman"; color: black; }a:link, span.MsoHyperlink { color: blue; }a:visited, span.MsoHyperlinkFollowed { color: blue; }span.il { }div.Section1 { page: Section1; }</style>
<div class="Section1">
<p class="MsoNormal" style=""><span class="il"><b style="">Allan</b></span><b
style=""> Sindelar</b><span style="font-size: 10pt;"><br>
<a href="mailto:Allan@positiveenergysolar.com"
target="_blank"><span class="il">Allan</span>@positiveenergysolar.com</a><br>
NABCEP Certified Photovoltaic Installer<br>
EE98J Journeyman Electrician<br>
<b style="">Positive Energy, Inc.</b><br>
3201 Calle Marie<br>
Santa Fe, New Mexico 87507<br>
<b style="">505 424-1112</b><br>
<a href="http://www.positiveenergysolar.com/"
target="_blank">www.positiveenergysolar.com</a></span></p>
</div>
</div>
<br>
On 10/20/2010 11:58 AM, jay peltz wrote:
<blockquote cite="mid:2EC57791-689B-4E67-A9A6-A8700481143C@asis.com"
type="cite">
<pre wrap="">Hi Ray et all,
The customer has 200' of 4/0 direct buried with a 24v system, and is running close to 60 amps now, and wants to add 6 more 215 watt modules.
So the issue has been to try and find a way around putting in another wire ie digging a new trench through his yard.
the client may be willing to try and see how it goes with the controllers, at this point hes aware that it could blow up and its not a warranty issue.
Will keep you up to date about what smokes or not.
j
peltz power
On Oct 20, 2010, at 10:18 AM, R Ray Walters wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Hi Jay;
I'd second (3rd, 4th?) everyone else's comments that it probably isn't a good idea.
I'd add that the diode will eat at least a volt, so that's not good for MPPT, or balancing.
The one possible way to do this, might be to use a Vanner battery equalizer, which is designed to split an incoming charge source, and feed 2 batteries, without letting them
"see" each other. I think they're only good for 24 v, though, so that might not work for your situation.
The only other way I could see, is using a huge relay ( or paralleled relays) controlled by a C40 (or similar). You would lose both MPPT and PWM, and be back in the solar stone age (90s) though.
TIme to pull out the 2 big cables, and pull 4 smaller ones?
Have fun, I actually like retrofitting old off grid stuff; it presents all sorts of interesting challenges like this.
R. Walters
<a class="moz-txt-link-abbreviated" href="mailto:ray@solarray.com">ray@solarray.com</a>
Solar Engineer
</pre>
</blockquote>
<pre wrap="">
_______________________________________________
List sponsored by Home Power magazine
List Address: <a class="moz-txt-link-abbreviated" href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a>
Options & 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>
List-Archive: <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-abbreviated" href="http://www.re-wrenches.org/etiquette.htm">www.re-wrenches.org/etiquette.htm</a>
Check out participant bios:
<a class="moz-txt-link-abbreviated" href="http://www.members.re-wrenches.org">www.members.re-wrenches.org</a>
</pre>
</blockquote>
</body>
</html>