Battery Hook-up

[Steve_B_]

OK, I am almost embarrassed to ask this but I will. I just bought a new battery for my little trailer. Recently I was in contact with an owner of another trailer like mine and inquired about hook up. He stated the contacts are hooked up opposite of how I have always hooked mine up. I haven't had any issues so I'm wondering- how do you tell which goes to positive and which to negative? There doesn't seem to be any red wire to guide me. Is something supposed to be marked? It's obvious in cars but this isn't so clear. Go ahead, you can you can tell me the obvious answer that I'm supposed to know!

[wa8yxm]

I will warn you that with 12 volt batteries even pictures are not always the do all end all, You MUST mark clearly the POSITIVE and NEGETAVE in the photo,, Make a sign and lay it atop the battery before you click the pic.

Here is why

As I said before.. you can get a Group xx in, usually, 3 (or more) Configurations

|=====|
|A . .|
| . .B|
|=====|

|=====|
| . . |
|A . B|
|=====|

Now Depending on the battery group SUFFEX, A may be Positive or Negative,, This is why the passing RVer said "Mine are hooked up the other way" His battery is hte reverse of teh O/P's. so at a glance, it appeared to the other person the O/P's battery was backwards.

Happned to me when I bought a new battery for my car.. The specified battery was a different suffex, so they put it in backwards. Was kind of impressive, Still have not figured out what smoked.

[CA_Traveler]

OP BEFORE you take anything else apart take pictures.

I have pictures on my laptop of lots of equipment and labels. Handy reference and invaluable when something comes apart.

[red31]

Older power centers in small trailers isolated the internal converter from the battery and lights work fine reversed, the furnace doesn't.

Generally the fuse near the batt is the positive.

[RJsfishin]

Traditionally,........
If you have red & black, red is positive.
If you have white and black, black is positive.

[RoyB]

Since AUTOMOTIVE WORLD battery cable colors and RV WORLD battery cable colors are not the same I always look at the battery case and find the WORD "NEG" or the symbol '-' and hand trace this connected battery terminal to make sure it is the one that goes to FRAME GROUND.

Some folks make a big mistake when they buy a new battery of the same brand and just hook it up like the old one was hooked up. Alot of times the newer battery will have the battery terminals relocated to the other side of the case which will make you rotate the battery in this case. Always checking the POLARITY words on the BATTERY case catches this situation pretty easy...

If you have two 6VDC Batteries connected in series then you have to look at the outside battery terminal connections for the NEGATIVE battery terminal going to FRAME GROUND.



If you have two 12VDC BATTERIES connected in parallel you should connect them in this manner to get best performance from the two batteries... This insures both batteries sees the same length of connected cables when producing load current and being charged as well. You wouldn't think a couple of inches in the LOAD path makes any difference but it most definitely does.


Just my thoughts
Roy Ken

[Old-Biscuit]

Steve B. wrote:
OK, there is a fuse on the side I have hooking up the positive post to, so it sounds like that is the right thing to do. I will check for the ground wire ASAP, another great suggestion.
Thanks!

Sounds like you have them hooked up correctly.......otherwise the converter reverse polarity fuses would have blown.

Get some colored tape, spray paint etc. and mark the positive cable so you have a reference for next time you take cables off.

[Steve_B_]

OK, there is a fuse on the side I have hooking up the positive post to, so it sounds like that is the right thing to do. I will check for the ground wire ASAP, another great suggestion.
Thanks!

[wa8yxm]

First, There is no STANDARD for color code, there is tradition, but no where is it documented, this can cause issues.

IF you have no problems, you are hooked up right, PERIOD, it's that simple.

NOW. Let us assume you have a Group 2N battery (24, or 27) or a 31.. All of these come in an "F" model and an "R" model, what is the difference.

The terminals are normally either at the front, or rear, edge of the battery, on (NOTE sometimes you get an "M" version too M is kind of like type O blood, universal donor) IF you put the positive terminal on the right, With one of the batteries the terminals will be near the front, and the other near the rear, IF you have an "F" and he has an "R" and he does not examine the battery (ALWAYS DO THIS) to find out which end is marked with a PLUS,,, he is simply wrong.

Page 2: Take a couple cans of spray paint and paint the wires red and black

IF.. you are putting a battery on a trailer with no clue...

Remove any and all fuses, MAKE SURE YOU LABEL THEM SO YOU CAN PUT THEM BACK.

ONE wires will show a dead short to clean metal frame parts (Hitch?)
Others will not.

Frame is Negative.

One way to tell if you have it right.

Negative probe or test lamp ground clip to the frame (Hitch?) positive probe or tst lamp tip to battery positive.

NOTE: with test lamp you can reverse connections. Either way if it's right it's bright.

[lanerd]

The best way is to see where each cable goes to. If it goes to the frame, it's a ground cable. If it goes through an in-line fuse and then into the trailer, it's a positive cable.

However, your best friend is a digital multimeter. Walmart, Harbor Freight, etc sells them for less than $20...the cheaper the better.

Take the meter and measure ohms and then put one probe on the cable connector and the other to ground. If it measures "1", then you have the ground cable...if it measures anything else, it's a positive cable. Simple, huh?

Ron