Switching 12v to dual six volts

[gbaglo]

#10 ground. I don't understand electricity, but that's what I was told by Reace. Guy who wired my RAV had to buy #10 wire ( charged me $25 extra ) because he normally uses #12.

[Brian B-P]

Electrical current flows in a closed circuit. It doesn't matter whether the wire is between the battery positive and the stuff being powered, or between that stuff and the battery negative, the current has to go through both of them, so resistance anywhere reduces the current flow for a given driving voltage.

The ground is an even bigger problem than the positive side of the circuit, because the current flowing in all circuits (the tail lights, the brakes, the "battery charge" which might be running a refrigerator...) all collects together and runs through that ground wire. In the seven wires connecting the tug to the trailer, the ground should be larger gauge than any of the others, or at very least as large as any of them.

For instance, this cable
Multi Gauge 7 Seven wire RV Camper Trailer Cable Cord Plug Conductor Cable
is probably intended for RVs, and has 14-ga for the lighting circuits, 12-ga for the brakes, 10-ga for the battery charge, and 10-ga to carry it all back on the ground connection.

This cable
Trailer Cable 7 Conductor 12/6-10/1 GA PVC Black Jacket
is probably intended for commercial trucks (using the 7-round-pin connector, not the RV-style connector) and has 12-ga for the lighting and auxiliary circuits, and again 10-ga for the ground shared by all of them. (Neither electric brakes nor battery charge are normally done via this type of connection.)

Here's one in which the thickest conductor is 8-ga... nice:
7 Wire Trailer Cable 4-12ga, 2-10ga. 1-8ga. By the Foot

[gbaglo]

Thanks Brian. Even I understood that.

[santacruzer]

So, if I'm understanding all this correctly, the trailer connector to the tow vehicle needs a 10 gauge ground wire, presumably to match the 10 gauge installed (hopefully) in the OEM tow wiring package? Wouldn't ETI be certain the trailer wiring harness had a 10 gauge ground wire when you order the 3-way fridge?

[mk1549]

Originally Posted by cpaharley2008

Nope, a retired government law officer. But I did sleep in a Holiday Inn Express awhile ago......

Love it

[skiman]

Originally Posted by cpaharley2008

Well it finally warmed up to where I can start doing some modifications. Today I pull out my group 29 battery and installed dual 6 volt batteries. These were purchased at Sam's Club, $84/each, total a/h capacity has been increase from 126 to 215 or useable from 50 to 90, not quite doubling my reserve capacity. I'm also going to add another solar panel since my unit came with the 95 watt solar. Need to wait until it gets warmer to attach to the roof.
I had ordered the extra capacity group 29 with the trailer and because of it's size Escape installed the larger battery box and longer cables. The dual six volts fit perfectly. I removed the dinette seat and the old battery. First you have to remove the 2x4 wood inside the box, slide the battery over and unscrew the box from the floor. This allows you to lift the battery right out.
I installed the dual sixers in series as well as the new Zamp Battery Check which attaches to the negative terminal. Batterycheck - Wireless RV & Marine Battery Management.
There is an APP you download to your iPhone/Ipad for diagnostics. Total time 2 hours.

Any feedback on the Batterycheck from your trip to Townsend?

[cpaharley2008]

Yes, it works fine and gives me all the info I need, however it's bluetooth range is only within the trailer, I was hoping to get the info while in the tow vehicle driving. Too far away for the bluetooth to pick up. Other than that I like it better than the Trimetic set up which involves running wires and cutting holes.

[skiman]

Thanks. Let us know more after Osoyoos.

[Buddy]

Planning on converting to the dual six volt batteries as well. Aside from 2 batteries, 2 new battery boxes, heavier wiring, possibly upgrading to a Batterycheck, etc. Is there anything else I should be upgrading or replacing i.e. chargers, inverters, etc.?

[gbaglo]

Best talk to ETI about this. I believe there are modifications to the frame, which is why they needed to know from the start if you wanted dual 6V. My understanding is that to make the change after the fact is extremely costly.

[cpaharley2008]

Unless you are putting them inside, then you will need a vented battery box.

[Buddy]

Originally Posted by gbaglo

Best talk to ETI about this. I believe there are modifications to the frame, which is why they needed to know from the start if you wanted dual 6V. My understanding is that to make the change after the fact is extremely costly.

Good idea. From what I can see, the modifications to the frame would be moving the spare tire carrier to the centre, adding a battery box support to the drivers side rear. The current battery box frame on the passenger side would need to be modified as well. Overall, fairly minor welding, unless there were some major changes to the frame as well.
No time like the present though. My 12 volt battery is not holding a charge for long so needs replacement regardless. I picked up two 6 volt battery boxes last year on a sweet deal, also have some surplus battery cable handy. A couple pieces of angle iron along with some square tubing, a little welding, some grinding, a little paint, and I should be in business. My biggest cost should be the new batteries.... Unless there is something else that I am not seeing.

[fudge_brownie]

Probably access to a hydraulic crimping tool and some heavy connectors. All your runs will be custom length and you want to minimize length. Eight gauge or less for main.

[strawbarry]

most electrical supply houses should sell crimp on connectors for the wire chosen and should have a loaner/ renta crimping tool for crimping them.

[Brian B-P]

Buddy, if you don't mind not taking advantage of your extra cable, and you want professionally crimped terminals on heavy-gauge cable, I have heard of suppliers who make up cables with whatever length and terminals you specify. I did a quick search in FiberglassRV where this was discussed, and although I didn't find a specific supplier, a search in eBay or whatever for "custom battery cables" should work, and I this post from FiberglassRV makes sense to me:

measure off the length you need, get the crimp ends and go to any large electrical contractor or wholesale outlet, they should be willing to do a few crimps with the hydraulic crimper for little or nothing. Most wholesalers would consider this a demo, and you might buy a roll or two of tape or some heat shrink or even the crimp ends while you're there.

Joe

... and this one:

Our local NAPA auto parts store makes custom wire by the foot, and crimps any style ends on it that you would like.

I have had a custom propane hose made up by an industrial hose supplier - they did the assembly, charged only for he hose and fittings, and do this routinely; electrical could easily be the same.

Personally, I would likely just connect the terminals to the cable myself. Crimping in large gauges is difficult; an alternative to hydraulic tools or professional services might be to use a compression type terminal (such as from QuickCable or the overpriced version from Monster Cable at auto sound shops) - a local industrial supplier carries the QuickCable brand and that is what I was planning to use for an aborted RV power project.

[steve dunham]

Manually hypressing lugs/ terminations on cable sized #1AWG and smaller is easy
Bundy makes an a crimping tool with an adjustable head for crimping different size lugs.
We often used #4 & #2 welding whip cable in battery applications ( electric forklifts- jumper cables -UPS systems ) ,it is highly flexible and the insulation is extremely tough .

[Brian B-P]

Originally Posted by steve dunham

Manually hypressing lugs/ terminations on cable sized #1AWG and smaller is easy
Bundy makes an a crimping tool with an adjustable head for crimping different size lugs.
...

I believe Steve. What I should have said is that crimping in large gauges is difficult without the right tool.
What's hard to believe is the price of these tools: $1444 and up Maybe I didn't find the reasonbly priced ones?
I suppose borrowing or renting is the solution... if large gauge connections are needed. For those in Wisconsin, maybe Steve's is available.

[fudge_brownie]

I found a hydraulic crimping tool on Amazon for under $40. It proved useful for the solar wiring I performed on my 21. It is not light and certainly not easy to fit into tight spaces but comes with a good variety of dies to fit almost any battery terminal connector available. I have more trouble finding a local source for the variety of connectors I needed. They are out there, I just have not found a single store with lots of inventory and variety.

Amazon Link

[Vermilye]

While not the least expensive solution, GenuinedealZ is where I've had my #0 inverter cables made. Excellent quality, your choice of color, and lots of terminal choices.

For those that prefer stranded 120V AC wiring, they supply Triplex AC Boat Wiring.

[Jim Bennett]

Originally Posted by Vermilye

For those that prefer stranded 120V AC wiring, they supply Triplex AC Boat Wiring.

I understand the reasoning behind the stranded wire for use in a vehicle, but has anyone heard of the solid wire actually failing in a trailer? I would think there would have to be a heck of a lot of vibration to cause failure, and I can only image what else would fail on a trailer with the same effects on it. I pulled the old stuff out of the '76 Trillium I am working on, and it was in great shape. I just plan on replacing with new solid #14 wire, as I have lots on hand.