I know that C&D battery does not like parallel strings and they have a device that measures the currents in each string
I investigated a fire from a battery bank of 48 volts 4 strings in parallel of 6 Volt 800 AH batteries. The parallel strings was indicated as bad practice and suspect as the cause of the fire. The battery bank was on a standalone system and had poor regulation on charging. (it was being charge controlled by a diversion controller) Also the fire in New Jersey was a parallel string case of 12 volt AGMs in 4 or more parallel strings (anybody remember better than I?). DT --- On Wed, 12/2/09, Tom Elliot <tell...@wagonmaker.com> wrote: > From: Tom Elliot <tell...@wagonmaker.com> > Subject: Re: [RE-wrenches] Strings and series of batteries > To: "RE-wrenches" <re-wrenches@lists.re-wrenches.org> > Date: Wednesday, December 2, 2009, 11:58 AM > > Message > > > > > > > > > > > I would be very curious to > hear THE battery > company's, or any battery company's, interest in > warranty on a system where the > strings of batteries are paralleled through a buss bar > rather than physically > through the bank. The vulnerability to failure of an > off-grid system with > only one or two series strings is high enough to be a > concern. Then > there's also the not un-trivial issue of handling large > batteries > safely. > > > > > > From: Tump > Sent: Wednesday, December 02, 2009 2:32 > AM > To: 'RE-wrenches' > > Subject: Re: [RE-wrenches] Strings and series > of > batteries > > > Surrette Battery, THE battery company > suggests NO MORE the 3 parallel > in a string & would like to see 2 > preferably. > If > there are more the 3 then they really not interested in > warrantee > issues. > Jamie > where are you?????? > > Now a > days there are plenty of options for a good size/AH BB that > can be configured in > 1 or 2 parallel strings. > Its just that us old guys are having a > harder time w/ > gravity! > > > t...@swnl.net www.SWNL.net > Solarwinds > Northernlights > Serving Mid > Coast Maine & Northern > California > Me.# 207-832-7574 Cl.# > > 610-517-8401 > > > > Blair "TUMP" > May > ******** > > MAINE'S CHARTER ******** > > > NABCEP "Certified PV > Installer" > > > ******** MAINE'S > CHARTER > ******** > Trace > Xantrex "Certified" Dealer / Installer" > > > > > > -----Original Message----- > From: > re-wrenches-boun...@lists.re-wrenches.org > [mailto:re-wrenches-boun...@lists.re-wrenches.org] On > Behalf Of > Dana > Sent: Tuesday, December 01, 2009 12:58 PM > To: > 'RE-wrenches' > Subject: [RE-wrenches] Strings and series of > batteries > > > > On a > similar subject here – > > > Long ago, I > had a Trojan battery rep. state that they did not like to > see more than [12] > L-16s in a series –parallel bank system. This was due > to too many points of > connection / resistance and bad communication > due to multiple flow > paths. > > > Has anyone > else heard similar or contrary > information/recommendations? > > > Thanks > > > > > > Dana > Orzel > > > Great Solar Works, > Inc > www.solarwork.com > E > - > d...@solarwork.com > V > - > 970.626.5253 > F > - > 970.626.4140 > C > - > 970.209.4076 > > > I > will be the shift > in how the world uses power! - Dana > Orzel > > > > > From: > re-wrenches-boun...@lists.re-wrenches.org > [mailto:re-wrenches-boun...@lists.re-wrenches.org] On > Behalf Of Larry > Crutcher, Starlight Solar > Sent: Tuesday, December 01, 2009 10:42 > AM > To: RE-wrenches > Subject: Re: [RE-wrenches] concord > batteries, EQUALIZE Them! > > > If the > 180 watt panel will > provide enough current to run the recovery process, then > give it a try. What I > expect is that your current will vary throughout the day. > Not sure if this is > a critical point or if it will just prolong the process. > Pay attention to the > temperature. I use a laser temp probe on the > terminals every 30 minutes > to verify. > > > > > > Another > thing to monitor is the > current. It will probably start very low and build > over time due to > high resistance from sulfated plates. During this time > the voltage might get > really high and then lower some. Don't worry about > the voltage. After a while > the current will begin to drop. This means the > recovery process is > working. > > > > > I just > realized that this > battery bank must be 4 in series and ten parallel > strings. This is a horrible > design that can never work right without extensive > monthly maintenance. The > strings with higher resistance will not be charged > properly. Because of this, > many strings will be undercharged every day. EVERY day! > So even if you recover > these batteries, someone will need to test and equalize > at least every month. > I really want to stress this point as multiple parallel > batteries are the ruin > and waste of many thousands of tons of batteries each > year. I never design for > more than two strings in parallel. Do this and be > happy. > > > > > > > > > > Larry > Crutcher > > www.starlightsolar.com > > > la...@starlightsolar.com > > > (928) > 941-1660 > > > > > > > > _______________________________________________ > List sponsored by Home > Power magazine > > List Address: > RE-wrenches@lists.re-wrenches.org > > Options & > 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 > > > > > > > No virus found in this incoming message. > Checked by AVG - > www.avg.com > Version: 9.0.709 / Virus Database: 270.14.89/2539 - Release > > Date: 12/01/09 09:32:00 > > > -----Inline Attachment Follows----- > > _______________________________________________ > List sponsored by Home Power magazine > > List Address: RE-wrenches@lists.re-wrenches.org > > Options & 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 > > _______________________________________________ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & 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
