<div dir="ltr">I second everyone. Center-tapping a 24 or 48v battery bank for 12v SEEMS like it should work just fine, especially for low load infrequent use like a 12v water pressure pump for a greenhouse, a weather station, etc.. Nope, I've been a loser every time, with that battery or pair always the first to go bad.<div><br></div><div>Samlex and Victron both make DC-DC converters I have had good luck with; they are thermally protected and you can stack multiple units for more amperage.</div><div><br clear="all"><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div style="margin:0px;padding:0px;border:0px;font-stretch:inherit;font-size:12pt;line-height:inherit;font-family:Calibri,Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(0,0,0)"><span style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:12.8px;line-height:inherit;font-family:Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(34,34,34)">Dan Fink</span></div><div style="margin:0px;padding:0px;border:0px;font-stretch:inherit;font-size:12pt;line-height:inherit;font-family:Calibri,Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(0,0,0)"><div style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:12.8px;line-height:inherit;font-family:Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(34,34,34)"><span style="font-size:12.8px">Executive Director, Buckville Energy Consulting</span><br></div><div style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:12.8px;line-height:inherit;font-family:Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(34,34,34)"><span style="font-size:12.8px">NABCEP PV Associate</span><span style="font-size:12.8px"><br></span></div><div style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:12.8px;line-height:inherit;font-family:Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(34,34,34)"><span style="font-size:12.8px">NABCEP Certified PV System Inspector</span></div><div style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:12.8px;line-height:inherit;font-family:Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(34,34,34)">IREC Certified Instructor\u2122 for: </div><div style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:12.8px;line-height:inherit;font-family:Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(34,34,34)">~ PV Installation Professional</div><div style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:12.8px;line-height:inherit;font-family:Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(34,34,34)">~ Small Wind Installer</div><div style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:12.8px;line-height:inherit;font-family:Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(34,34,34)"><span style="font-size:12.8px;font-style:inherit;font-weight:inherit">NABCEP Registered Continuing Education Providers</span><br></div><div style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:12.8px;line-height:inherit;font-family:Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(34,34,34)"><a href="mailto:dan.fink@greendustrialtraining.com" target="_blank">d</a><a href="mailto:anbob88@gmail.com" target="_blank">anbob88@gmail.com</a></div><div style="margin:0px;padding:0px;border:0px;font-style:inherit;font-variant:inherit;font-weight:inherit;font-stretch:inherit;font-size:12.8px;line-height:inherit;font-family:Arial,Helvetica,sans-serif,serif,EmojiFont;vertical-align:baseline;color:rgb(34,34,34)">970-672-4342</div></div><br> </div></div></div></div></div></div></div></div></div></div></div></div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Dec 31, 2019 at 10:57 AM Ray <<a href="mailto:ray@solarray.com">ray@solarray.com</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>
<p>Even with battery balancers, battery tapping is still a really
bad idea. I know, I did it on my own system in the 90s. The
DC/DC converters are the way to go, but be sure and over size it
by a fair amount to handle the fridge starting surge.
Unfortunately my favorites are no longer available: made by Solar
Converters in Canada. I've seen them last decades. Iota should be
good stuff, their chargers have long term reliability. Samlex
inverters have been around for quite a while too, but I don't have
long term experience with their converters. <br>
</p>
<pre cols="72">Ray Walters
Remote Solar
303 505-8760</pre>
<div>On 12/31/19 10:05 AM, Dave Angelini
Offgrid Solar wrote:<br>
</div>
<blockquote type="cite">
<p>Tapping a battery bank is not a good practice. it will
unbalance the bank. Much better to add a 24V electronic
converter for the 12V loads. Then replace the 12V loads when
time permits. They will need a spare converter so buy 2. Amazon
has tons of these converters. Your quote is great BTW. H N Y !</p>
<pre> </pre>
<pre><strong><span>Dave Angelini Offgrid Solar
"we go where powerlines don't"
<a href="http://members.sti.net/offgridsolar/" target="_blank">http://members.sti.net/offgridsolar/</a>
e-mail <a href="mailto:offgridsolar@sti.net" target="_blank">offgridsolar@sti.net</a>
text 209 813 0060</span></strong></pre>
<p>On Tue, 31 Dec 2019 11:52:20 -0500, Chris Schaefer
<a href="mailto:chris@solarandwindfx.com" target="_blank"><chris@solarandwindfx.com></a> wrote:</p>
<blockquote type="cite" style="padding-left:5px;border-left:2px solid rgb(16,16,255);margin-left:5px;width:100%">
<div dir="ltr">G'day and Happy New Year to All,
<div> </div>
<div>Recently came across this offgrid OB FX system. The first
part is a 12v battery system w/ 2 PV modules, 2 Trojan L16
batteries used to power a frig and freezer about 6 years
old. The second is a 24v with 3kw of PV, 4 Trojan L16's,
twin OB FX inverters installed by an HVAC contractor back in
2016. This was their first offgrid project. Oh boy, lol. The
client would like to add more battery capacity to both. My
thought here is since we are powering only a 12v frig and
freezer why not simplify the system by creating a single
battery bank and then tapping off of the 24v bank using
proper fusing and creating a 12v buss? Admittedly I live in
a 48v world so I'm asking our esteemed colleges as to
options on how to address this. </div>
<div> </div>
<div>Oh yeah, the installer is unresponsive (no surprise
there) and they are also having firmware issues with an old
Mate 3 and would like me to install a new Mate 3s but that's
another issue I'll tackle when I head out to site. </div>
<div> </div>
<div>Thanks All,</div>
<div>Christopher- <br>
<div dir="ltr">
<div dir="ltr">
<div>
<div dir="ltr">
<div dir="ltr">
<div dir="ltr">
<p style="text-align:center"><span style="font-size:10pt;color:rgb(31,73,125)"><span style="font-family:Arial,sans-serif">Chris
Schaefer's<br>
</span></span><a style="font-size:12.8px" href="http:www.solarandwindfx.com" target="_blank"><img style="color: rgb(31, 73, 125); font-family: Arial, sans-serif; font-size: 10pt;" src="http://www.solarandwindfx.com/wp-content/uploads/2015/01/Solar-Wind-FX-Logo.png" alt="" width="200" height="40"></a><br>
<em><span style="font-family:Arial,sans-serif;color:rgb(31,73,125)"><span style="font-size:9pt">Tel/Fax
585-229-2083 or Cell 585-748-1870 </span><span style="font-size:12px"><br>
</span></span></em><em style="font-size:12.8px"><span style="font-size:10pt"><span style="color:rgb(31,73,125)"><span style="font-family:Arial,sans-serif">5115 South Hill Road ~
Canandaigua New York 14424<br>
</span></span></span></em><em style="font-size:12.8px"><span style="font-size:10pt"><a href="http://www.solarandwindfx.com" target="_blank"><span style="color:blue">www.solarandwindfx.com</span></a>
~ E-mail: <span style="color:blue"><a href="mailto:chris@solarandwindfx.com" target="_blank">chris@solarandwindfx.com</a></span></span></em></p>
<p style="text-align:center"><em><span style="font-size:10pt"><img src="http://solarandwindfx.com/wp-content/uploads/2015/01/certs.jpg" alt="" width="200" height="56"><br>
</span></em></p>
<p style="text-align:center"><span style="font-size:10pt">Thomas Jefferson,
the author of our great Constitution, once
said, "democracy" will cease to exist when
you take away from those who are willing to
work and give to those who would not."</span><span style="font-size:10pt"></span></p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</blockquote>
<div>-- <br>
<pre> </pre>
</div>
<br>
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