Pictures of my dual GV2 battery setup.

[Atlee]

I replaced the Group 24 battery (85 amp/hour) with a pair of GC2 batteries (215 amp/hour) from Sam's Club. I also used a 2 gauge wire to connect the two batteries. The battery box is from Century Plastics. It was a bit pricey but it fit perfectly. All the much, much cheaper single 6V battery boxes were too large to fix the battery rack on the trailer. I got the battery box from Ebay.

[SoundGuy]

SoundGuy wrote:
Don't understand why Century insists on manufacturing these battery boxes in white plastic instead of conventional black as does NOCO. :h

Atlee wrote:
I would have preferred black, no doubt, but unfortunately, this Century box was the only one I could find that would fit in the battery box holder.

Yeah, it's curious as to why NOCO doesn't offer their single 6 volt battery box in a double length dual 6 volt version. :h

[Atlee]

I would have preferred black, no doubt, but unfortunately, this Century box was the only one I could find that would fit in the battery box holder.

SoundGuy wrote:
Don't understand why Century insists on manufacturing these battery boxes in white plastic instead of conventional black as does NOCO. :h

[Atlee]

The black wire to the positive post is the Barker power wire. This powers the Barker power jack. All the power jacks I've had, had a black positive power wire.

The positive and negative cables are both the same size, 6 gauge. Maybe an optical illusion since the picture was taken at an angle.

Matt_Colie wrote:
Altee,

The job is real clean and in coming years you will realize the effort was well spent.

There are some minor things
Not only is Gordon right about "Where's the fuse?", but you have a black wire going to a positive post. At least get some read tape to mark it. That is the kind of thing that will get screwed up when you least can afford it.
In the pictures, it looks like the cables to the bank are different sizes. While this may never matter, If you have charging difficulties, this could be a factor.

I have been changing owners boats that had paralleled 12V over to 6V in series until the money ran out a few years back. To a man, they saw an improvement in the available house power.

Matt

[Atlee]

No question replacing the wires from the battery to the converter back in the trailer would be a good thing, but I wasn't up to the task of running new wire. It would have meant pulling off the Coroplast underbelly cover to get to the wires. maybe in the future.

I'm hoping the new heavy duty batteries and greatly increased amp/hours will provide for some longevity and extra power when boondocking. Also, I hope the new PD4655 converter with Charge Wizard will also help in keeping the batteries charged and topped off.

I know heavier wires would be a great benefit. Maybe a future project.

DrewE wrote:
Looks very good to me. You'll find that it's a good improvement over what you had before, no doubt.

The 2 gauge wire is probably heavier than you need, but there's certainly no harm in that. Replacing the leads to the RV with heavier ones would have greater benefit (but also greater cost and greater difficulty in installation).

[Atlee]

Same place it was before with the 12V 85 amp/hr battery, on the front edge of the trailer chassis.

Here is a picture of the electrical junction box on the front of the chassis.

GordonThree wrote:
Sorry to be "that guy", but where's the fuse?

[SoundGuy]

GordonThree wrote:
I'm glad your psychic powers confirmed the presence of a current interrupting device.

Since the OP has a 2017 Jayco Jay Flight 23RB it doesn't take "psychic powers" to confirm the presence of a current interrupting device - whether you agree with it or not this trailer will be wired with an auto reset breaker in the positive cable coming from the battery. As for upgrading to a heavier "fuse", sure he could, but there's not much point if he doesn't also upgrade the wiring from the battery back to the converter, which is most likely 6 gauge at best.

[azrving]

ktmrfs wrote:

SoundGuy wrote:

Matt_Colie wrote:
Not only is Gordon right about "Where's the fuse?"...

Why would the OP need a "fuse" when no doubt that positive battery cable running back to the trailer first goes directly to a resettable circuit breaker, most likely mounted on the trailer's A-frame. That's the "fuse". I'd agree though, regardless of the colour of wire used I'd mark each as POS and NEG for ease of identification. 🙂

well, on the fuse. First, it's highly likely that the trailer fuse
1) is an automatic reset, which means it will open, close, open close....get the picture for a short
2) highly likely it is not rated to interupt the current that the battery bank can deliver and can end up not being a fuse but a welded shut contact
3) won't protect if the battery cable shorts BEFORE the trailer fuse.

On my trailers I have a appropriate sized and rated fuse at or very near the battery bank.

And second, I replace the typical factory trailer breaker with one that is NOT automatic reset, but manual reset.

This is seldom considered but those clicker type breakers are terrible. As you say, when there is a fault they heat and open over and over until the contact tips weld and then take out a circuit. I have repaired many wiring harnesses which melted down because of these breakers. They are cheap so that's the good reason they are in RV's.

[GordonThree]

kd7kbk wrote:
Battery mounted fuse

Designing 2 different battery systems for my 5th wheel and my house to power my Ham Radio shack with a SGC-500 PowerCube Amp. It can pull 90A. Safety first with large battery banks that you can basically arc weld with.

That's a pretty slick fuse system. I'll have to remember that the next time I'm wiring up some heavy duty DC.

[kd7kbk]

Battery mounted fuse

Designing 2 different battery systems for my 5th wheel and my house to power my Ham Radio shack with a SGC-500 PowerCube Amp. It can pull 90A. Safety first with large battery banks that you can basically arc weld with.

[ktmrfs]

SoundGuy wrote:

Matt_Colie wrote:
Not only is Gordon right about "Where's the fuse?"...

Why would the OP need a "fuse" when no doubt that positive battery cable running back to the trailer first goes directly to a resettable circuit breaker, most likely mounted on the trailer's A-frame. That's the "fuse". I'd agree though, regardless of the colour of wire used I'd mark each as POS and NEG for ease of identification. 🙂

well, on the fuse. First, it's highly likely that the trailer fuse
1) is an automatic reset, which means it will open, close, open close....get the picture for a short
2) highly likely it is not rated to interupt the current that the battery bank can deliver and can end up not being a fuse but a welded shut contact
3) won't protect if the battery cable shorts BEFORE the trailer fuse.

On my trailers I have a appropriate sized and rated fuse at or very near the battery bank.

And second, I replace the typical factory trailer breaker with one that is NOT automatic reset, but manual reset.

[GordonThree]

SoundGuy wrote:

Matt_Colie wrote:
Not only is Gordon right about "Where's the fuse?"...

Why would the OP need a "fuse" when no doubt that positive battery cable running back to the trailer first goes directly to a resettable circuit breaker, most likely mounted on the trailer's A-frame. That's the "fuse". I'd agree though, regardless of the colour of wire used I'd mark each as POS and NEG for ease of identification. 🙂

I'm glad your psychic powers confirmed the presence of a current interrupting device.

[SoundGuy]

SoundGuy wrote:
Don't understand why Century insists on manufacturing these battery boxes in white plastic instead of conventional black as does NOCO. :h

drsteve wrote:
Same here. They are going to look like c rap in a few years when the algae and black mildew discolors them, like the white propane tank covers they used to foist on us.

It's just a matter of esthetics and I guess some like white but to me it looks dorky, no different than white propane tank covers. 😞 However, black plastic tank covers, tongue jack head covers, battery boxes, etc, can still fade over time from constant exposure to the sun. After repainting my tank cover I solved this issue by covering the entire tongue jack anytime the trailer is parked and we're not using it. This cover has faded badly but all the black plastic parts underneath haven't at all. :B

[drsteve]

SoundGuy wrote:
Don't understand why Century insists on manufacturing these battery boxes in white plastic instead of conventional black as does NOCO. :h

Same here. They are going to look like c rap in a few years when the algae and black mildew discolors them, like the white propane tank covers they used to foist on us.

[SoundGuy]

SoundGuy wrote:
Don't understand why Century insists on manufacturing these battery boxes in white plastic instead of conventional black as does NOCO. :h

mike-s wrote:
A cooler battery is a longer lasting battery.

You seriously believe that's why these Century boxes are white and not black like every other battery box on the planet? :@ Seriously? :R