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Topic: What is the best method of connecting multiple batteries ? (Read 2850 times) previous topic - next topic

Re: What is the best method of connecting multiple batteries ?

Reply #25 –
Must be lots of fun skiing all over the place!!!!
We have a neice who could not get to work driving her BMW there in Sudbury (west Boston) so she sold it and got a new R Rover Evoque!! Must be bad I guess. We have too much sun down here so I wonder if a trade off could be made??
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: What is the best method of connecting multiple batteries ?

Reply #26 –
After reading the article, I decided to check my battery wiring.  The 2 engine batteries are connected using method 2.  The house battery wiring is a puzzle? The neg terminals are on the left side of the batteries and the positive on the right side.  There are jumpers from neg to neg and pos to pos.  There is only one neg cable from somewhere in the motorhome and it is connected to the left battery.  There are 4 positive cables (2 large and 2 small) and 1 large and 1 small are connected to each battery.  The large pos cable to the left battery is connected to the large fuse above the battery compartment.  So what method is this #1 or #2?
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt

Re: What is the best method of connecting multiple batteries ?

Reply #27 –
Jerry, you show two 8A8D's in parallel.
Mogan David
1999 U295 36'

Re: What is the best method of connecting multiple batteries ?

Reply #28 –
Quote from: Mogan David –
Jerry, you show two 8A8D's in parallel.
Yes, all three methods have the batteries in parallel and mine are in parallel, but what is the method of connection?
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt

Re: What is the best method of connecting multiple batteries ?

Reply #29 –
Well, I didn't get much response from the forum on this, but I think I have it figured out.  Appears to be a combination of method 1 and 2; if that is possible.  Moving the large and small positive cables from the left to the right battery and leaving the jumpers in place would make it method 2.  May need to buy longer bolts for the right positive battery connector.  No doubt it would be a lot neater with all the positive cables on a bus bar, but that means installing a bus bar and a cable to the battery.  Anyone else have this arrangement?  I may have shifted the connections when I replaced the batteries 7 years ago.  I know from the posts that some of you have installed a bus bar.
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt

Re: What is the best method of connecting multiple batteries ?

Reply #30 –
I have the problem solved.  I had a piece of heavy wall 3/4 " copper tubing that I converted into a mini bus bar on the battery post connector.  It was rigid copper so I heated it with a torch to soften, then squeeze it flat in a vise; then drill some holes for the bolts.  With all the positive cables on the bar, it is definitely method # 2. 
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt

Re: What is the best method of connecting multiple batteries ?

Reply #31 –
Jerry,
 
Is your battery tray on rollers, or do you have to overcome gravity and friction to pull it out?
 
Thanks,
 
Trent

Trent and Jean Eyler
2000  U295  4003  WTFE  ISC  350
Build#5603 MC#17385

Re: What is the best method of connecting multiple batteries ?

Reply #32 –
It's like extra heavy duty drawer slides with ball bearings and it has a lot of grease on the slides.  I'm guessing about 20 lbs of force to pull it out.  One bolt has to be removed to pull it out.  After the last post I decided it would be better to have the heavy cables in the middle of the bar.  Both of these 7 yr old MK 8A8D batteries do not have much capacity left and need replacing.  I plan to buy 8G8D as the gel battery can take a deeper discharge and more recharge cycles than the AGM. 
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt

Re: What is the best method of connecting multiple batteries ?

Reply #33 –
A follow up on this thread.  Right after my last post discovered that one of the batteries had a bad cell or at least I think that was the problem.  With batteries disconnected and isolated one dropped to 11.7 volts and the other stayed at 12.5.  Used just the good battery on our trip; no dry camping, so it could handle our needs.  Searched the internet for MK 8G8D and Marine Battery.com had the best price, placed an order, and they showed up about 10 days later on a 54' R & L semi trailer.  Packed on a pallet with shrink wrap.  Trailer had a lift gate.  Driver called and I met him at the intersection as I knew he could not make it down the street and turn around without a lot of trouble.  He said he would roll them down the street with his pallet jack and leave it at the drive, but I convinced him that it would be much quicker and easier for the both of us to put them in the back of my car.  He even took the pallet.  Link to Marine Battery website said free shipping, but I did pay shipping.  $1253 with shipping.  Marine Battery is really an Apex Super Store website.  I charged them and after sitting overnight both show 13 volts.  My brother-in-law helped me swap them out.  Sold the old ones for $21.35. 

Now that they are installed, I realize that these batteries do not have a hold down like all car batteries do.  My chassis batteries on the coach have that.  Does your coach have a hold down on the house batteries or is it like mine? 
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt

Re: What is the best method of connecting multiple batteries ?

Reply #34 –
Its called Series Parallel connection.
The series connection increase Voltage and the Parallel connection increases Amperage. Therefore a Series Parallel connection increases both Volts and Amps.
In a Series connection you connect a Negative to Positive and a Parallel connection you connect Negative to Negative and Positive to Positive.  Leaving one Negative and one Positive terminal to connect to your equipment.

Just type "Series Parallel Battery Connection" in your search engine and it should produce link with diagrams.

PS, Don't forget to grease the terminals with a non graphite grease..

Re: What is the best method of connecting multiple batteries ?

Reply #35 –
Quote from: Jerry Whiteaker –
Does your coach have a hold down on the house batteries or is it like mine? 
Jerry,
 
My house batteries do not  have a hold down either.
 
Trent
Trent and Jean Eyler
2000  U295  4003  WTFE  ISC  350
Build#5603 MC#17385

Re: What is the best method of connecting multiple batteries ?

Reply #36 –
In the real world, minimize the number of connections/cables (unless it's an extra ground cable) and don't worry about rotating the batteries. There are already enough problems from corrosion and associated high resistance so don't make more by making the installation more complicated than necessary. In probably over 90 percent of the time, good intentions for cleaning terminals, etc. go out the window once the installation has been made, only to surface months or years later when a problem occurs. Using high quality terminals components along with careful installation are the key to the least amount of problems.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: What is the best method of connecting multiple batteries ?

Reply #37 –
Quote from: Pierce & Gaylie Stewart –
In the real world, minimize the number of connections/cables (unless it's an extra ground cable) and don't worry about rotating the batteries. There are already enough problems from corrosion and associated high resistance so don't make more by making the installation more complicated than necessary. In probably over 90 percent of the time, good intentions for cleaning terminals, etc. go out the window once the installation has been made, only to surface months or years later when a problem occurs. Using high quality terminals components along with careful installation are the key to the least amount of problems.

Pierce
I agree with what you said, but I was just trying to kept it simple and not have to buy new cables, install bus bars, etc.  I suppose we should not have any roll over accidents or these 155 lb batteries will be flying around near the fuel tank. 
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt
 

Re: What is the best method of connecting multiple batteries ?

Reply #38 –
Jerry,

Was making a general statement. Example would be using military type terminals with the two sets of fasteners compared to the stock set. They only cost a couple of bucks more but provide a more secure connection. As I remember, Ken installed them with photos on his U300. When you have the set of cables with the terminals already installed, some good stainless hardware is a step up from the mild steel they come with. Cuts down on the corrosion and won't end up eaten away.

I melted a set of terminals starting without a block heater at high altitude with the temps in the teens. Changed over to heavy duty fasteners as well as making the cable contact area as flat and clean as possible so the max amps can flow through with the least possible resistance. Many batteries come to a bad early end because of poor cable ends/fastener condition.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)