[RE-wrenches] Tri-Star MPPT

Wed Jul 24 07:31:48 PDT 2013

Hi Jay,
This has happened to me personally, and to other customers I have dealt 
with over the years. In my case, I got my hands 
on (4) used Interstate Workaholic L16 batteries. I was unable to achieve 
an acceptable SG because the voltage would not
climb above 14V (using 20A charger). I used a clamp-on DC amp meter to 
verify a full 20A going into the batteries, but the voltage
 would not climb any higher. It was as if energy was being lost within the 
batteries. When I separated the bank into sets of two, 
the ratio of current-to-capacity was improved and I was able to equalize 
the daylights out of them, and eventually recovered 
their performance. I have heard of the condition where the battery has low 
SOC, and the charger causes the voltage to increase 
very quickly, but I cannot definitely attribute that to sulfation. It 
sounds more like an internal open circuit condition. I do know it 
usually results in the need to replace the batteries. 
Rgds
_____________________________________________________________________________________ 

Eric Bentsen  |   Schneider Electric   |  Solar Business  |   UNITED 
STATES  |   Technical Support Representative 
Phone: +(650) 351-8237 ext. 001#  |   
Email: eric.bentsen at schneider-electric.com  |   Site: 
www.schneider-electric.com/solar  |   Address: 250 South Vasco Rd., 
Livermore, CA 94551 

*** Please consider the environment before printing this e-mail 

From:
jay peltz <jay at asis.com>
To:
RE-wrenches <re-wrenches at lists.re-wrenches.org>
Date:
07/23/2013 07:33 PM
Subject:
Re: [RE-wrenches] Tri-Star MPPT
Sent by:
re-wrenches-bounces at lists.re-wrenches.org

Hi Eric,

While agree with most all your assessments, 
Can you please elaborate on the "sulfation causes the voltage not to 
climb?"

This is quite counter to what I have seen and what the battery people say?

Thanks

Jay

Peltz power

Sent from my iPad

On Jul 23, 2013, at 2:48 PM, Eric.Bentsen at schneider-electric.com wrote:

Hi William, 

 If the SG was 1.26, of course the battery voltage would increase 
quickly to >30V (which is high for warm weather, BTW). 
 It has been my experience that sulfation causes the voltage NOT to climb. 
Especially when you have a very large bank, and a 
 relatively small amount of solar. 
 Sometimes it is necessary to reduce the bank size into smaller sets to 
equalize them and recover their performance. 
This method of reducing bank size is also effective to compare performance 
and weed out a potentially bad battery. 
 Systems that have a lot of capacity, with a relatively small amount of 
charge current usually creates problems, because 
 the load demand exceeds solar production. 
 This results in batteries that operate with partial SOC, which is when 
sulfation is most prevalent. With (8) L16s, you have approx 
 800Ahrs of capacity (24V bank). It would take significantly more than 8A 
of charge current to properly care for a bank that size. 

Rgds,
_____________________________________________________________________________________ 

Eric Bentsen  |   Schneider Electric   |  Solar Business  |   UNITED 
STATES  |   Technical Support Representative 
Phone: +(650) 351-8237 ext. 001#  |   
Email: eric.bentsen at schneider-electric.com  |   Site: 
www.schneider-electric.com/solar  |   Address: 250 South Vasco Rd., 
Livermore, CA 94551 

______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
______________________________________________________________________
_______________________________________________
List sponsored by Home Power magazine

List Address: RE-wrenches at lists.re-wrenches.org

Change email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

List-Archive: 
http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org

List rules & etiquette:
www.re-wrenches.org/etiquette.htm

Check out participant bios:
www.members.re-wrenches.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20130724/2fe94f6e/attachment-0004.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 11065 bytes
Desc: not available
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20130724/2fe94f6e/attachment-0004.jpe>