How do you insure proper charge voltage to the 12 v set? Never tried
that one.
Ray Walters
Remote Solar
303 505-8760
On 1/2/20 1:37 PM, Chris Worcester wrote:
I would like to add that you don’t need to get rid of the 12 v battery
bank, but use it for the high amp draw buffer, like a large capacitor.
Then use the DC to DC converter between the two battery banks. Done
this for years on multiple off grid systems.
Chris Worcester
Solar Wind Works
NABCEP PV Installation Professional
Office 530-582-4503
Cell 530-448-9692
www.solarwindworks.com
ch...@solarwindworks.com
*From:*RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org]
*On Behalf Of *Tom Duffy
*Sent:* Wednesday, January 01, 2020 8:55 AM
*To:* RE-wrenches
*Subject:* Re: [RE-wrenches] combining 24v and 12v systems
Agree! use a Victron DC to DC Converter
Kind regards
**
*Tom Duffy*
*/Senior Solar Design Engineer/*
**
*If you don’t have the Time or Money to do it right in the first
place, how will you get the Time and Money to fix it?*
TSBLOGODPIx500x200
*t...@solar-biz.com <mailto:t...@solar-biz.com>*
*MAIN TOLL FREE:**888-826-0939*
*DIRECT:**888-503-6772*
*International:**001-575-539-2111*
*PANAMA:**507-836-5588 X 122*
*FAX: 520-844-8442*
*/www.thesolarbiz.com/*
*From:* RE-wrenches <re-wrenches-boun...@lists.re-wrenches.org> *On
Behalf Of *Allan Sindelar
*Sent:* Tuesday, December 31, 2019 6:51 PM
*To:* RE-wrenches <re-wrenches@lists.re-wrenches.org>
*Subject:* Re: [RE-wrenches] combining 24v and 12v systems
Agreed: no 12v tap. I’ll add (with modest experience, as this doesn’t
come up as an upgrade very often any more) that Mean Well, despite the
odd name, proved itself pretty reliable in some early Wattsun tracker
drives and some other DC-DC applications. Available online; see
https://www.meanwell-web.com/en-gb/dcdc-converters/
Allan
On Dec 31, 2019, at 10:46 AM, Dan Fink <danbo...@gmail.com
<mailto:danbo...@gmail.com>> wrote:
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.
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.
Dan Fink
Executive Director, Buckville Energy Consulting
NABCEP PV Associate
NABCEP Certified PV System Inspector
IREC Certified Instructor™ for:
~ PV Installation Professional
~ Small Wind Installer
NABCEP Registered Continuing Education Providers
d <mailto:dan.f...@greendustrialtraining.com>anbo...@gmail.com
<mailto:anbo...@gmail.com>
970-672-4342
On Tue, Dec 31, 2019 at 10:57 AM Ray <r...@solarray.com
<mailto:r...@solarray.com>> wrote:
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.
Ray Walters
Remote Solar
303 505-8760
On 12/31/19 10:05 AM, Dave Angelini Offgrid Solar wrote:
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 !
*Dave Angelini Offgrid Solar*
*"we go where powerlines don't"*
*http://members.sti.net/offgridsolar/*
*e-mail offgridso...@sti.net <mailto:offgridso...@sti.net>*
*text 209 813 0060*
On Tue, 31 Dec 2019 11:52:20 -0500, Chris Schaefer
<ch...@solarandwindfx.com>
<mailto:ch...@solarandwindfx.com> wrote:
G'day and Happy New Year to All,
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.
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.
Thanks All,
Christopher-
Chris Schaefer's
Image removed by sender. <http://www.solarandwindfx.com>
/Tel/Fax 585-229-2083 or Cell 585-748-1870 //
//5115 South Hill Road ~ Canandaigua New York 14424//
//www.solarandwindfx.com
<http://www.solarandwindfx.com> ~ E-mail:
ch...@solarandwindfx.com
<mailto:ch...@solarandwindfx.com>/
/Image removed by sender./
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."
--
_______________________________________________
List sponsored by Redwood Alliance
List Address:RE-wrenches@lists.re-wrenches.org
<mailto:RE-wrenches@lists.re-wrenches.org>
Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive:http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
<http://www.re-wrenches.org/etiquette.htm>
Check out or update participant bios:
www.members.re-wrenches.org <http://www.members.re-wrenches.org>
_______________________________________________
List sponsored by Redwood Alliance
List Address: RE-wrenches@lists.re-wrenches.org
<mailto:RE-wrenches@lists.re-wrenches.org>
Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive:
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
<http://www.re-wrenches.org/etiquette.htm>
Check out or update participant bios:
www.members.re-wrenches.org <http://www.members.re-wrenches.org>
_______________________________________________
List sponsored by Redwood Alliance
List Address: RE-wrenches@lists.re-wrenches.org
<mailto:RE-wrenches@lists.re-wrenches.org>
Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive:
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
<http://www.re-wrenches.org/etiquette.htm>
Check out or update participant bios:
www.members.re-wrenches.org <http://www.members.re-wrenches.org>
_______________________________________________
List sponsored by Redwood Alliance
List Address: RE-wrenches@lists.re-wrenches.org
Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive:
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out or update participant bios:
www.members.re-wrenches.org
_______________________________________________
List sponsored by Redwood Alliance
List Address: RE-wrenches@lists.re-wrenches.org
Change listserver email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive:
http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out or update participant bios:
www.members.re-wrenches.org
