Solar ring connectors to a 2 battery bank

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marcortez

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Jul 31, 2015
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141
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Desert SouthWest
2 TT house batteries wired in parallel....A frame mounted
From a portable solar panel kit with charge controller.
Instead of gator clips on the batteries, use ring connectors to the posts.
Proper connection scheme?....one ring on one batteries positive and the other ring on batt# 2 negative?

Or both rings on the pos/neg of a single batt and let the parallel connection send charge to both?

Seems to me, a hardwired ring connection that can be left on the batteries is a better deal than gator clips?
 
Proper connection scheme?....one ring on one batteries positive and the other ring on batt# 2 negative?

Yes, because doing so equalizes both batteries. If you were to connect to only one of the batteries, that battery would wind up charging and discharging at a different rate then the 2nd one.

I found this helpful: http://www.smartgauge.co.uk/batt_con.html
 
Not true!  As long as the jumper cable is in place on the neg.terminals of both batteries and the jumper cable is in place on the pos. terminals....both terminals are at the same potential with respect to the other terminals.
 
Batteries that are wired in parallel have all the positives posts tied together, similarly all the negatives are tied together. This works regardless of how many batteries are in the bank.

Given that, it doesn't really matter which specific post you tie to.

Electricity will find the path of least resistance regardless of which battery post you tie to. Balance of the batteries is affected more by defects in the system than where you place the charge wires. For example if the wires tying the batteries together are too small that would be considered a design defect and that can cause charge imbalances. Any defect should be fixed, post placement choice is not a fix.
 
        ^^^^^^        100% Accurate.  Just make sure that the terminals are clean and not corroded, the battery terminals are tight, and of course the wire is of the proper gauge for the load placed on it.
 
Everything I've read indicates that if you attach your battery leads to a single battery that battery will be overworked relative to the other batteries in parallel or series. See image
 

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First of all, there's a night and day difference between a parallel hookup and a series hookup.  A parallel hookup allows you to get the same 12VDC , but doubles your A/H availability (if you are using two batteries).  If two 6 volt (think golf cart) batteries are hooked in series, you get 12VDC and the same A/H

Secondly, that drawing/picture in the above post is is fine, BUT the explanation is totally wrong.  Current flow happens when:
1.  There is a complete circuit (nothing in the circuit path open)
2.  When there is a potential applied to the circuit (12 volts in our case)
3.  The resistance in the circuit is not so great to overcome or stop current flow with the applied voltage or potential.

What you are failing to understand is that any point of the negative side of the circuit is at the same electrical potential as any other point in the negative side of the circuit.  And, conversely, any point of the positive side of the circuit is at the same electrical potential as any other point in the positive side of the circuit.  Of course this is given the fact that there are no loose connections anywhere or corroded terminals, or some defect inside one of the batteries.  Any other explanation DEFY ohms law......and that ain't happening.
 
xrated said:
  A parallel hookup allows you to get the same 12VDC , but doubles your A/H availability (if you are using two batteries).  If two 6 volt (think golf cart) batteries are hooked in series, you get 12VDC and the same A/H

Two (2) 6V batts wired in parallel gets 12V and double or the same Ah as one batt?

Two 225 Ah batts now get 450Ah if wired parallel?......and 12 V?
 
marcortez wrote:
Two (2) 6V batts wired in parallel gets 12V and double or the same Ah as one batt?


NO!!! batteries wired in PARALLEL maintain the voltage (in your case 6V.).  The capacity (if 225ah) doubles to 450amps/hours available at 6 Volts.

If two 6V batteries are wired in SERIES, the voltage adds up ( to 12V in this case). The capacity remains at 225 amp/hours at 12V.
 
marcortez said:
Two (2) 6V batts wired in parallel gets 12V and double or the same Ah as one batt?

Two 225 Ah batts now get 450Ah if wired parallel?......and 12 V?

I DIDN'T say two 6 volt batteries in parallel!  Two 12 volt batteries in parallel will give you 12 volts and double the amp hours available

Two 12 volt batteries in SERIES will give you 24 Volts and the same amp hours of the rating for one battery
 
Alfa38User said:
marcortez wrote:

NO!!! batteries wired in PARALLEL maintain the voltage (in your case 6V.).  The capacity (if 225ah) doubles to 450amps/hours available at 6 Volts.

If two 6V batteries are wired in SERIES, the voltage adds up ( to 12V in this case). The capacity remains at 225 amp/hours at 12V.

I think he thought I was talking about 6 volt batteries in my parallel example. I've reposted for clarification purposes.
 
Desert_Rat said:
Everything I've read indicates that if you attach your battery leads to a single battery that battery will be overworked relative to the other batteries in parallel or series. See image
I fully believe that to be an urban myth.

Charging wires from panels or alternator are typically considerably smaller than the cables that connect the batteries together. That small wire from the charging source is a limiting factor. The big cables between the batteries can handle typically 4 to 8 times more juice so there should be no impediment to either battery doing it's share.

Voltage can be thought of a bit like water pressure in that to charge if your charge source is putting out 14.5 volts and battery A is charged to 14.5 and battery B is at 14 volts only battery B will continue to accept more charge. The charge source simply balanced against battery A.

Happens the same way on discharge if Battery A is at 12 volts and B is at 12.5, B will take more load until they balance.

Defects in the system like improperly sized wires, loose connections, dirty connections, low acid levels, contaminated acid, damaged cables, ... , are much more likely problems.
 
markbarendt said:
I fully believe that to be an urban myth.

I beg to differ. It is also said the chain is only as stong as its weakest link. Many places for a weak link to occur in a multiple battery set up. Your scenerio assumes a perfect "chain". Not reality. Too many variables.

In reading the thread word for word, it appeared to me the OP has 2 6v batteries. But he doesn't confirm that fact. He never says type of batteries he has. Sounds to me like everyone is guessing.

I think it's a good time to start again. Lets find out exactly what the OP has in place (Maybe pics?) and help this poor poster out. 
 
denmarc said:
I beg to differ. In reading the thread word for word, it appeared to me the OP has 2 6v batteries. But he doesn't confirm that fact. He never says type of batteries he has. Sounds to me like everyone is guessing.

I think it's a good time to start again.

There is no reason to start anything over.  He has TWO 12volt batteries.  You could have a dozen of whatever voltage batteries you want to talk about, and if they are all in parallel, you can put the charging leads wherever you want....as long as the negative lead is somewhere on the negative part of the battery array........and the positive lead is somewhere on positive part of the battery array....it makes absolutely NO difference and will charge the battery bank.  Obviously, one regular sized battery charger trying to charge 12 batteries in my example is going to take a while, but that is because you now have 12 Times the available Amp/ Hours of just one single battery

And by the way, the original poster has TWO 12 volt batteries.....not 6 volt batteries! 
 
He doesn't state specifically that he has two 12V batteries, but by simple deduction, it's there.  A couple of keys to this....
1.  He has TWO batteries
2.  He has stated that they are connected in PARALLEL

So this is how I know he has 12V batteries.....

What is the voltage of two (or more) 12 volt batteries connected in parallel................12 Volts
What is the voltage of two 6 volt batteries connected in parallel....................6 volts

So now it become crystal clear, as I don't know of any RVs that run on a 6 volt system.....so the obvious answer is two 12 volt batteries.  Hope this helps.
 
OP here....

Two 6 volt batteries wired to put out 12volt.
I was mistaken to wire in parallel. They should be in series.

The original Q was to what terminals on the batteries to connect ring terminals from a portable solar panel/charge controller.

I think this has been answered.......

 
marcortez said:
OP here....

Two 6 volt batteries wired to put out 12volt.
I was mistaken to wire in parallel. They should be in series.

The original Q was to what terminals on the batteries to connect ring terminals from a portable solar panel/charge controller.

I think this has been answered.......

Well that changes everything.  You have no choice on where you put the terminals from the charger.... You do have a 12V charger.....right?
 
xrated said:
Well that changes everything.  You have no choice on where you put the terminals from the charger.... You do have a 12V charger.....right?

Yes.....the solar panel with charge controller will put out the 12V when out and about.
When not on the road, a 12V battery maintainer.

 
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