I am putting in water in two of my six batteries at very rapid rate. Why only two that are going through the water?Diver - 11-9-2008 at 09:42 AM
Are you running the same wire size to all of your batteries ?
If these 2 are the first in the line and the rest are connected with a higher resistance wire, they may overcharge with your controller connected to
the "bank".
Just a thought; I had this problem once.
Maybe some electrician-type can tell you how to check the charge to each battery to find out ?Russ - 11-9-2008 at 09:45 AM
I've found the two on either end use more than the rest. Some others I've talked with have the same thing or only the one on positive end. Right now
with all my batteries the same age the water use seems to be about equal though.
Edit: Make sure all the terminals are very clean and see if that makes a difference.
[Edited on 11-9-2008 by Russ]TMW - 11-9-2008 at 10:06 AM
As batteries age their internal resistance builds. The battery or batteries with the highest resistance will have the highest charging voltage across
it and therefore produce more heat and use more water. That's why when using multiple batteries in series they should be replaced all at once. If
mixing batteries use a voltmeter to monitor the voltage drop across each battery.BajaGringo - 11-9-2008 at 10:10 AM
I have heard that it is best to replace all the batteries at once but if you need to add a couple of batteries to put them on the ends to get the most
life out of them. It is something I am looking to put together myself right now until we are on the grid at our new place...Bob and Susan - 11-9-2008 at 11:12 AM
what kind of batteries?
how do you have them wired?
are the wires the same size?
where are the tow that use the water located?
what is your charge controler set to for the float?
when was the last time you equalized?
what voltage do you equalized at and how long?
Quien Sabe ?
MrBillM - 11-9-2008 at 03:27 PM
This MAY be one of Life's great unanswerable questions.
For at least the last Sixteen years, my MAIN battery array has consisted of 10-12 PAIRS of Golf-cart batteries. Until 2005, they were ALL the same
Brand (Interstate). There are NO variables involved in wiring, equalization or maintenance between the various individual units.
Over those Sixteen years, I have found them to weaken, use additional water or fail with no rhyme or reason. At present, I have 1-pair left from 2003
and 3-pair from 2004 which are fine and exhibit normal water usage. I have 2-pair from 2005 and 1-pair from 2006 that use water at a higher rate, but
still load test fine. My suspicion would be manufacturing variances, but
WHO KNOWS ?Bob and Susan - 11-9-2008 at 03:47 PM
what kind of batteries?
if you mix brands or sizes... batteries act "weird"
you should replace the batteries all at one time if possible
how do you have them wired?
if you wired them incorectly you could be charging them incorectly
(ex: there is two ways to link 24v together one is correct one is not...both work)
are the wires the same size?
if you use different size wires you increase or decrease voltage
where are the two that use the water located?
in my string the two closest to the neg lead get the least charge
what is your charge controler set to... for the float?
the factory sets the float too low to protect the controller
and an inexperienced user
when was the last time you equalized?
equalization makes all the batteries have the same charge and boil away the sediment...or it's supposed to
what voltage do you equalized at and how long?
again the controller usually is set too low or too high and the time can be set for how long...if it's a current model and not an dinosaur
bill you probably don't use that much electricty to notice these things
the ONLY to check the condition of the batteries is with a hydrometer...
and that thing isn't always a true reading
i'd just keep filling the water up as long as you have enough electricty to last the night and morning
enjoy the electricty
i'll bet you if some are too "hot" and some not so "hot" because of one of these questions
Experts and Otherwise
MrBillM - 11-9-2008 at 04:49 PM
This is another one of those subjects where everyone who has ever connected two wires becomes an expert willing to freely distribute advice. Said
advice is often worth exactly what it costs.
As far as Equalization goes, THAT is also a subject which everyone freely expounds on even if they haven't the slightest idea what processes are
actually involved. Equalization is looked upon as some sort of mystical process which will somehow cure whatever ails the array. There is plenty of
actual Technical Information available and I would STRONGLY suggest that you personally read and UNDERSTAND the process yourself before doing so.
Ditto for the Controller Info regarding Bulk and Float settings for battery types. DON'T depend on what someone else says without reading it.
Xantrex and others publish the information. Read it. Sometimes, people throwing advice around know Zip about Electrical theory. The bottom line
regarding all of the Controller Crap is that those settings affect the ENTIRE array and do NOT explain variations between individual batteries.
As far as individual batteries within the same array charging at a different rate, THAT IS an indication of either extreme distance between the batts,
inadequate wiring cross-section or both. In most cases (such as mine) the TOTAL distance from one end to the other is about Eight feet. While I use
"0" gauge cable, the usual two-guage would likely work fine. Bigger is better in this case.
I have measured the differences in charge value from one extreme end to the other and the fractional differences are so insignificant, they are of no
import.
While maximum efficiency is best achieved when all units in the array are the same type and value, I've found NO practical differences over the years
on my array (or the many others I've worked on) to indicate that better efficiency is obtained by replacing ALL of the units at one time as opposed to
replacing those as they go weak.
In any case, with Internet access, there is no reason to buy any free technical advice when there is more than enough REAL expert information.
Speaking of which, here is a decent explanation of Equalization. I've got a technical bulletin from Trace (now Xantrex) which is more-detailed, but
this is good enough.
Equalization is required to mix the battery acid and bring every battery plate to an equal charge. Equalization should only be performed when required
or once every six months. Equalization is required when the cell specific gravities vary from highest to lowest by +/- 0.015 (1.245 - 1.260 at full
charge). The exact particulars (such as charging time and currents) are dependent on the charging system. However, the point is to bring the batteries
up to the equalization voltage and continue charging for 1-2 hours at a low current, without excessive heat. The final or finishing charging current
should be 3-7% (we recommend 5%) of the 20 hr capacity in amps. If battery temperature exceeds 125ºF the battery should be taken off of charge and
allowed to cool before equalization is continued. When two consistent specific gravity readings are taken a half hour apart the battery is equalized.
It is recommended to water the battery cells before or half way through the equalization. This is to assure the water is completely mixed into the
electrolyte.Bob and Susan - 11-10-2008 at 06:46 AM
first of all the question was...
why do 2 batteries use more water than the rest ???
address that question here
the rest of this "banter" is only an opinon
using outdated Trace (now Xantrex)
equipment and data
[Edited on 11-10-2008 by Bob and Susan]BajaRob - 11-10-2008 at 07:42 AM
One possible solution, if not already in place, is to charge the batteries at one end of the bank and to take power to the DC load and inverter from
the opposite end of the bank. This helps assure full flow through the bank. Not rocket science, just common sense.Pompano - 11-10-2008 at 08:19 AM
I LIVE IN THE SOLAR SYSTEM.
I have batteries. They are of dubious intent and not to be trusted around small children.
Not that this will help you with your current issue, but you can move your batteries on a regular basis from the ends into the center of the rows,
pushing the other batteries out towards ends, say every 6 to 12 months.gnukid - 11-12-2008 at 03:37 PM
Quote:
Originally posted by BCSTech
Not that this will help you with your current issue, but you can move your batteries on a regular basis from the ends into the center of the rows,
pushing the other batteries out towards ends, say every 6 to 12 months.
Hi
Just wondering, BCS Tech, Do you maintain certifications for Solar electric installations? If so which? If not is it because you do not find them to
be of value to you? Just wondering what certifications/experience would provide you with good experience to troubleshoot and install? Thx. I really
want to know for future projects...BigWooo - 11-12-2008 at 03:52 PM
If you haven't solved your battery problem yet, this bulletin board is very informative:
I agree, BigWooo. It's a great forum. Due in part to great advice on this forum, I just bought 6-130w Kyoceras, , 12 Crown batts, an inverter, and
a controller from N. Ariz Wind & Sun for a northern off-grid home.
Lots of great hints on battery maintenance, replacement schedules, etc.
p.s. And the prices were the best of a dozen bidders.
