Batteries

[grant1]

I plan to put 2 six volt golf cart batteries in my 5th wheel, how do i connect the two together?

 

[MPBerk]

CONNECTING BATTERIES IN PARALLEL, SERIES and SERIES-PARALLEL



This is really simple, but it's amazing how many folk screw it all up!



In series, volts increase; amps remain the same.

In parallel, amps increase; volts remain the same.



In Parallel: you connect the (+) of one batt to the (+) of the other. Connect (-) of one to the (-) of the other. You will then have still have a 6 volt batt, but with greater amp hour capacity. This is now an ordinary 6 volt batt, except that instead of being in one "box," it is in two boxes.



In Series: If you were to hook two 6 volt batteries in series, you'd have 12 volts. However, using 6 volt (usually golf cart) batteries. E. G. , Two 105AH 6v in series would still = about 105AH but @ a nominal 12V.



Wiring in Series:

To visualize it easier. Start with a simple block diagram. Two 6V batteries.

On left batt, place (-) at left end, place (+) on right end.

On right batt, place (-) on left end, place (+) on right end.

Draw a line from (+) on left bat to adjacent (-) on right bat.



This is now an ordinary 12V bat, except that instead of being in one "box" with cells all connected in series on the interior, it is in two boxes joined with a cable. It's still a single 12 volt bat, electrically, so START THINKING OF IT THIS WAY and don't confuse yourself by thinking of it as bat 1 and bat 2.



At this point, you've got two unused bat posts -- just like an ordinary 12 volt bat; one neg that goes to chassis ground and one pos that goes to normal 12V isolator/supply/etc.



Series/Parallel:

Just repeat the series step above with two more 6 volt batts and you end up with two 12V batts. Think of it this way instead of as four 6V batts! You now have two (-) unused posts. Connect them together (just as you would when connecting two ordinary 12V batts in parallel). Repeat for the two unused (+) posts.



It's really quite simple. The problem many people have is in thinking that this is very complicated. It's not.



The only time you think of the batts as four 6V bats is when you disconnect them for maintenance and cleaning. And then, only to make absolutely certain that you don't screw up when putting them back together.

Toward this end, it's essential that you clearly label posts and cable ends!



... ... and a site with plentiful tips http://www.phrannie.org/battery.html ... ... ... ... ... ... . good luck

 

[LandShark]

In series for a 12 volt system. You will need a short (about 12" depending on how you locate the batteries) piece of battery cable with proper end terminals to connect the positive pole of one battery to the negative pole of the other battery. The remaining available positive pole connects to the positive (should be red) cable from the rv and of course the remaining negative pole connects to the negative (SHOULD BE BLACK), rv cable.



Be very carefull!!! If you screw this up, you can melt the terminals and connectors, burn yourself, or even blow up the batteries!!!



If you're not sure, get some help. Find yourself a book on basic electricity.

 

[Gary - K7GLD]

Simply, assuming a common 12 volt circuit, the positive wire that originally went to the positive post of the original 12 volt battery will now go to the positive post of one of the new 6 volt batteries - and the negative wire will go to the negative post of the OTHER 6 volt battery - THEN, using a wire at LEAST as large in conductor size as those already connected to the batteries, connect the unused negative post of one 6 volt battery to the unused positive post of the other one.



Done!

 

[KMeek]

I am still laughing. I read the post from MPBerk and thought to myself, "this guy must be an engineer to make something this simple so complicated". Sure enough. Then Gary and Landshark come along and reduce the answer to simplicity. Nice answers from all of you! I am still laughing though!

 

[klenger]

Here's my (engineer's) crack at the explanation:



Hook 'em up like batteries in a flashlight. [- +] [- +]

 

[Gary - K7GLD]

BUT GEE Ken, flashlight batteries are only 1. 5 volts...

 

[klenger]

Some people's kids!!

 

[EnLjones]

which connection

Ok now that we have all or that straightened out... can someone please tell me why or when one would want to wire up batteries like that? Which way is the best way to hook up my trailer batteries. . or is it just 'battery' since they are hooked together?

 

[Prairie Dog]

You'd wire up batts like that if they were 6 volts.

Two six volt batts in series = 12 vdc, two 6 volt bats in parallel = 6 vdc.

 

[OTRPU]

Unless you're starting with 12V Deep Cycle batteries.



Cheers,

Steve J.