Two battery set-up

I bought a switch that allows me to choose either battery or both or neither. Since my batteries are of two different sizes, I don't intend to ever use them at the same time, but the switch allows it if/when I replace them. My idea is to use my primary (larger), but always keep the 2nd battery as a spare in order to be able to run the slides, tongue jack and emergency brakes should I run the primary down too far.

valhalla360 wrote:
Assuming your original battery hasn't been abused (ie: drained dead or very low), you can probably just get another battery of similar size and wire it in parrallel (tie the two positives together and the two negatives).

6V wired in series (positive from one to negative of the other) would be nice option if your current battery was near the end of it's life.

Normally, you want to change out all the batteries at once because if one has problems, it tends to draw down the new battery and quickly wear it out, so if there are any indications that your existing battery isn't in tip top condition, replace it.

Google images of wiring batteries in parrallel and it should get you some drawings of how to wire it.

X2
If you decide to go the 6v route, your best bet is to get 2 GC-2 golf cart batteries at Costco or Sam's Club

You may find The 12 Volt Side of Life helpful.

Assuming your original battery hasn't been abused (ie: drained dead or very low), you can probably just get another battery of similar size and wire it in parrallel (tie the two positives together and the two negatives).

6V wired in series (positive from one to negative of the other) would be nice option if your current battery was near the end of it's life.

Normally, you want to change out all the batteries at once because if one has problems, it tends to draw down the new battery and quickly wear it out, so if there are any indications that your existing battery isn't in tip top condition, replace it.

Google images of wiring batteries in parrallel and it should get you some drawings of how to wire it.

Oops! :o

Two 6 volt batteries wired in series would yield 12v. and the maximum available amp hours. A pair of 6 volt batteries would likely be heavier that than 12 volt batteries, but don't know how much more weight.

I run 2 group 27 12v. batteries hooked up in parallel on our TT when we're dry camping. I got 2 1/2 days on them with careful power management, including running the furnace as needed, which thankfully isn't needed that much down here in the winter..........

I did have to modify the battery box mounting to get the two battery boxes in. Both of them wouldn't fit sitting in the factory installed angle iron welded on the tongue.

Raptorx9 wrote:
I am wanting to add a second battery to my TT to increase the amount of time I can run off of 12 volt. Anyone else done this and what size batteries should I be looking at??

Two 6 volt batteries wired in series would yield 12v. and the maximum available amp hours. A pair of 6 volt batteries would likely be heavier that than 12 volt batteries, but don't know how much more weight.

I run 2 group 27 12v. batteries hooked up in parallel on our TT when we're dry camping. I got 2 1/2 days on them with careful power management, including running the furnace as needed, which thankfully isn't needed that much down here in the winter..........

I did have to modify the battery box mounting to get the two battery boxes in. Both of them wouldn't fit sitting in the factory installed angle iron welded on the tongue.

I added a second battery to my TT by welding in a new longer frame to hold two plastic battery cases. I used 8AWG wire and connectors to hook in parallel to the original battery. Remember the wiring may be different than automobile wiring. Some RVs use black and white--- Black positive with white negative

yes...well I hope it is. It is a 2014 TT so I would assume the battery is new, but I guess I am not really sure.

Is your current battery fairly new?