No, Tom I am not sure that I know the difference between bus bars and cable paralleling.
But I do know that warmer batteries have a lower voltage than cold batteries, this difference is even greater for sealed than flooded. If one battery has a higher temperature than another battery that it is in parallel with the warmer battery will get a greater charge current, the cooler battery will get less charge current. The more charge current AND it will generate more heat. Then the warmer battery well get warmer still and have an even lower voltage and have a higher current, making it warmer still. If it goes to far the paralleled batteries will start to dump power into the hot battery and you have thermal runaway, which is always bad news. But even if you do not go to runaway, you have a temperature based uneven charging. --- 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, 2:00 PM > Darryl, > > Do you understand the difference between paralleling the > "traditional" > off-grid way through the bank and using a buss bar? > That was my question. > The installations are quite different. > > Tom > > -------------------------------------------------- > From: "Darryl Thayer" <daryl_so...@yahoo.com> > Sent: Wednesday, December 02, 2009 8:26 AM > To: "RE-wrenches" <re-wrenches@lists.re-wrenches.org> > Subject: Re: [RE-wrenches] Strings and series of batteries > > > 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 > > > > > > > > > > > No virus found in this incoming message. > > Checked by AVG - www.avg.com > > Version: 9.0.709 / Virus Database: 270.14.90/2540 - > Release Date: 12/01/09 > > 21:33:00 > > > _______________________________________________ > 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
