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Topic: Coach battery charging (Read 676 times) previous topic - next topic

Coach battery charging

With a 3 battery bank, can you hook a battery charger conditioner to one battery in series and have it charge all 3?
Thanks, Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: Coach battery charging

Reply #1 –
Yes
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Coach battery charging

Reply #2 –
Well sort of,  Three 12v batteries in a battery bank are connected in parallel.  If you are going to connect a battery charger to the battery bank connect the + charge cable to the + post on the battery at one end of the three and the - charge cable to the - post on the battery at the other end of the three.

This is the preferred way to connect to batteries wired this way as are both the start and house batteries in your coach.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Coach battery charging

Reply #3 –
Quote from: Roger & Susan in Home2 –
Well sort of,  Three 12v batteries in a battery bank are connected in parallel.  If you are going to connect a battery charger to the battery bank connect the + charge cable to the + post on the battery at one end of the three and the - charge cable to the - post on the battery at the other end of the three.

This is the preferred way to connect to batteries wired this way as are both the start and house batteries in your coach.
Interesting Roger...why is this the preferred way...?
Hans & Marjet
1995 U300 "Ben" (#4719)
3176B Cat,4060HD,Jake
SKP#139131
Motorcade#17579
2006 Honda Element (towed)

Re: Coach battery charging

Reply #4 –
Each battery has internal resistance.  If you connect loads or chargers to the two terminals at one end of the three the discharge or charge to the second one one will be less than the first and much less to the third.  Hooking loads or charging to opposite corners helps to balance (not perfectly) loads or charge.

Here are some reference documents on battery stuff.  And a picture from BatteryTender.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Coach battery charging

Reply #5 –
Thanks for the info.  That is what I will do.
Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: Coach battery charging

Reply #6 –
Roger, if 1 battery in that group being charged in your diagram has a bad cell, would that protect the other batteries? 
I had 6 of 8 8D batteries in my Newell go bad because 1 or more had a bad cell and caused all to overcharge.  Don't remember the way it was wired but probably not that way.
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Coach battery charging

Reply #7 –
I think when a cell goes bad there is lots of bad stuff that can happen.  There must be a good way to discover them earlier than later.

I think the best way to connect your batteries is one battery at a time to a common bus bar with all equal length cables.  The way they did it from the factory years ago was an OK solution for two or three battery banks.  Loads are not equal nor will lifetimes be.  When you go to four batteries in parallel it gets worse.  In the coaches FT is building today all batteries hook up to a common bus bar.  I did my two pairs of 6v (in series) that way
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN