Correct battery cable hook up

oldpa · 04-01-2010, 12:08 PM

I just replaced my house batteries in a '03 Sightseer and have read the cables should be installed so that they are "balanced". Is picture A or B the right way? Or is it some other way?

Thanks, Greg

andrew619 · 04-01-2010, 12:24 PM

B would be the right one

Rick Long · 04-01-2010, 12:59 PM

They are both the same....

Harry B · 04-01-2010, 01:28 PM

The configuration in picture B has the correct connections

wirelessenab · 04-01-2010, 01:34 PM

B is better. See SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

Belgique · 04-01-2010, 08:40 PM

One of the drawings for your Winnie that are on this site depicts the correct way. You'll have to search on it for your rig.

autofish · 04-01-2010, 08:54 PM

B is right

DAN L · 04-02-2010, 12:28 AM

Quote:

Originally Posted by oldpa

I just replaced my house batteries in a '03 Sightseer and have read the cables should be installed so that they are "balanced". Is picture A or B the right way? Or is it some other way?

Thanks, Greg

i vote for B, although there seems to be very little difference. the example #2 in smart gauge electronics does seem to provide a benefit.

check this resource, chapter 7.
Electrical Tutorial

wirelessenab · 04-02-2010, 04:35 PM

Quote:

Originally Posted by DAN L

i vote for B, although there seems to be very little difference. the example #2 in smart gauge electronics does seem to provide a benefit.

check this resource, chapter 7.
Electrical Tutorial

Big difference especially if the cables connecting the batteries are too small, ie higher resistance. In any case for diagram A the battery with both coach leads connected to it will be working harder than the other battery. If the interconnect leads are small or the connection points are high resistance the one battery could be doing most of the work with the other battery along for the ride.

Get the resistance from the interconnect cables and do the calcs. You will be surprised.

oldpa · 04-03-2010, 02:11 PM

Thanks for all the help.

Greg

wa8yxm · 04-04-2010, 03:19 PM

B is the "Balanced" one

However unless you have a major power sucker like a 2000 watt inverter balancing is way overrated... Just so you know

At anyting less than 100 amps, the jumper cables you use to connect them will show so little voltage drop that balancing is a "non-issue"

At more than 100 amps.. Well.. I'd have to do some testing.

But in practice.. The need for balnace.. Applies to life, Martial Arts, and many other things.. but not batteries.

(In this life, there must be balance.. So my teacher said to me.. Living life is the point of things and balance is the key) (Crane Dance. By Julia Ecklar)

dirko · 04-05-2010, 04:00 PM

Hi Ho: As WA8YXM poinits out a difference of maybe 18 inches isn't really critical. If you have #2 AWG wires (they look about that big in the picture) and you draw 100 amps (that's a lot) there is only about 30 mv. difference. You could have that much difference due to the condition of the battery terminal of wire lug.

Anyway B gives about the same length for both batteries to the load, so "why not?". It is probably more important to use the same batteries (type, age, etc.) and make sure the contacts are clean, tight, etc.

Dirk

RJay · 04-05-2010, 04:42 PM

I believe it has more to do with the internal resistance of the batteries. In picture A both positive and negative leads originate at the same battery so more of the load will come from that battery. When the positive lead of the battery is moved to the other battery(picture B) the internal resistance of both batteries will divide the load currents equally. With more batteries added to the bank each battery will have a slightly different internal resistance so consequently the loads totals for each battery will vary slightly as the Smart Gauge website shows.

hdossett · 04-05-2010, 09:13 PM

B is the Best Balanced Batteries. All current flows the same distance, charge or load. Makes batteries happier!

Harold

rowesort · 04-06-2010, 09:36 AM

I have mine hooked up as in B and the 4 Trojan 105's batteries are now 6 yrs old and hooked up to roof mounted solar panels. Just had the cable ends replaced and the batteries tested at 85% of original. So just like tires proper maintenance and continous us they can last a lot longer than a lot of RV ers think.

Replaced my Michellins at 7 yrs and 58,000 miles, The tire shop did an inspection after the tires were off and were in good shape and had a few years left in them.