Why Twin 6V?

[Brian B-P]

Originally Posted by dave macrae

Two 6 volt wired is series to provide a 12 V source is a much larger capaicty than even two 12 volt batteries and are more suited to the rigors of rv use.

This is not true, in a fair comparison; that is, if you compare any number of 12V batteries with a pair of 6V batteries from the same product line of the same manufacturer and of the same total weight, they will have about the same performance in every respect.

The problem is that people often compare two 6V batteries with a much smaller 12V battery, or compare 6V batteries built for serious commercial deep-cycle duty to lightweight consumer-grade multi-purpose "marine/RV" batteries.

The most common and practical reasons for choosing two 6V over one 12V seem to be:

• one battery large enough is too heavy to lift, so the same capacity split in two cases is more manageable
• commercial-duty 6V batteries intended for golf cars are readily and inexpensively available, while the equivalent 12V models are less common and so more expensive

If a two-battery setup is chosen (for any reason), 6V in series act like one battery, while 12V in parallel don't necessarily share the load and charging equally - the series set are easier to manage.

[hotfishtacos]

Jim, his manual probably calls for that wire gauge. My 2500 watt inverter called for 3 gauge so Reace pulled 3 gauge into the cabin for me. It is what the manual calls for. I do agree also with the statements regarding wire gauge between batteries. I made my battery cables from 4 gauge which is plenty for the application.

[Jim Bennett]

Boy, without doing the math, if one was to pull this 2,500 to 3,000 watts power, even dual batteries would not last long, I would think. You gotta excuse my amazement, it is just something way beyond what I thought that one would need. Though, as said before, these trailers are a huge move towards luxury for me, as opposed to having to rough it.

[dave macrae]

the 3000 watt inverter is over kill for what we need could get away with a 2000 for our small coffee pot and my wifes hair dryer and such but the 3000 is simialr money to the 2000 and who knows what the future may hold.

[Jubal]

Two 12V batteries may be better for short term inverter use as more total amp hours are available.
Wiring 6 Volt Batteries in Series - Solar RV Panels

[Vermilye]

As Brian said, the voltage of the batteries does not matter as much as the design & construction. There are deep cycle 12V batteries that are just as capable as 6V, but they are a bit harder to find, and as he stated, in a size that provides the same amp/hrs as a pair of 6V, heavy. A pair of Trojan T 105 6V batteries will provide 225 amp/hrs & weigh 62 lbs each. A single equivalent of the pair would be a Trojan J185H-AC 12V, also 225 amp/hrs, but it weighs 128 lbs, more than I'd want to lift. Of course, 2 of these would provide 450 amp/hrs, far more than a pair of 6V...

One additional difference - a single T105 sells for around $130.00 (of course you would need 2) while a single J185H-AC 12V is around $400.00.

As to wiring, my 17B came with #10 wire between the batteries & running to the converter. I added a 1000w inverter & replaced the wiring between & from the batteries with #0, the recommended size by Xanterx. I then ran #10 wire (with a 30 amp breaker) between the inverter & the converter. One point with inverter wiring - if you use normal wire size tables to calculate the current capacity of the input wiring, you may find your inverter shutting down because it senses low battery voltage. It doesn't take much voltage drop over the wiring to cause the problem. If you expect to load your inverter near its capacity, don't skimp in the wire size.

[Brian B-P]

I think Jon has illustrated the practical application of the choice nicely.

Just to build on this example a bit more:

Originally Posted by Vermilye

A pair of Trojan T 105 6V batteries will provide 225 amp/hrs & weigh 62 lbs each. A single equivalent of the pair would be a Trojan J185H-AC 12V, also 225 amp/hrs, but it weighs 128 lbs, more than I'd want to lift.

... and that pair of T105 weigh the same (124 lb) in total, but they are individually more manageable.


If you need 225 amp-hours, the classic "pair of golf cart batteries" makes sense... and weighs a lot simply because it is a lot of capacity. If you will use 50 amp-hours over a typical weekend of camping before the next opportunity to charge, or to tide you over before the solar panels can get the charge caught up again, do you need that much battery capacity? If you only need to carry 120 amp-hours, you don't need to split it into 2 battery cases; on the other extreme, if you need 400 amp hous, you're likely looking at four batteries to get that capacity in units that you can lift.

[dave macrae]

We have always used our honda 2000 watt generator for our higher wattage short term power needs and it has worked fine, altthough it does idle up alot while my wife uses the hair dryer, the one she was using was drawing 1500 watts, I found one that draws under 1000 for this year, I was hoping that with our solar panel set up and twin volts and a inverter in the trialer we could minimize the use of the honda. we have never needed more than it will do but the price of the 3000 versus the 2000 watt inverter are minimal. I guess I will have to see if twin 6volts will have enough , I suspect they will as it will all be short term use of the inverter.

[J Mac]

Dave, Your wife could just let her hair dry in the sun. That would be solar....wouldn't it?

[dave macrae]

Oh shes come along way since we met but I have been told the hair dryer is a sticking point. Hows that go happy wife happy life ?

[cpaharley2008]

Another thought, keeping your set up to 12v would allow a spare tug battery ICOE.

[barry]

My wife uses the propane furnace in the trailer as her hair dryer (it took a lot of convincing!!) and then the 300 watt inverter works for her hair straightener ....... works like a charm as far as I'm concerned ...............

Barry

[hotfishtacos]

Originally Posted by Jim Bennett

Boy, without doing the math, if one was to pull this 2,500 to 3,000 watts power, even dual batteries would not last long, I would think. You gotta excuse my amazement, it is just something way beyond what I thought that one would need. Though, as said before, these trailers are a huge move towards luxury for me, as opposed to having to rough it.

Remember Jim the idea is not to run that amount of power over long periods of time but to be able to run convenience items like a blender that draws 400 watts or an electric grill that pulls 14 amps aren't on for hours but short periods of time. The inverters need thick power cords to operate correctly..pretty simple!.

[Jim Bennett]

I do understand the size of cable needed for a current draw, it is more the need for the power that has me surprised. Things like a blender or electric grill have never entered into my realm of consideration.

It is obvious some disagree with my way of thinking, that is fine, but I really do like to keep it fairly simple, and not haul along a lot of stuff (weight) when there are other simpler ways of dealing with things.

If you are a full timer, and living in your trailer it would be somewhat different, but I am just using it for relaxation and adventure, and not much for luxuries are really needed. For me, striving for simplicity trumps striving for luxury for when I go camping. For me it is truly an 'Escape'.

[Vermilye]

In my case I could get away with a 300 watt inverter for my computer, various chargers, even an electric blanket. The reason for the 1000 watt inverter is for my mug of drip coffee each morning. Silly, but I do live in the trailer for months at a time...

[dbailey]

I generally agree with the "keep things simple" philosophy. But, there are occasions when a bit of luxury is fun. Got a glamping weekend with the girls? Bring along a blender for margaritas... A bunch of families getting together for a weekend? Maybe bring along a screen, projector and video player to show a scary camping movie.

Not something I'd do every time, but a nice-to-have on occasion.

[Jim Bennett]

We get together with large groups of family and friends many times a year. Daytime is usually filled with a bit of work if we are on our land, and a whole bunch of wild sporting events like all-terrain bocce, horseshoes, frisebee, and playing in the water. Evenings are always a big campfire with a few guitars brought out. Even in the worst of weather we set up around the fire, and just make it as big as needed, and add a couple big tarps for rain.

We have done the margarita thing, but just buy one of those buckets you add the tequila and (I think) water too. Toss it in the freezer overnight, and scrape out some good magaritas the next day.

I love smoothies for breakfast, and do miss those while camping. We do take a small gen set sometimes though.

[Bruce Wray]

If you're truly desperate for a camping smoothie or blended margarita, but don't want to engage in headache-inducing industrial rewiring discussions and/or modifications, there's this option: https://www.lehmans.com/p-4719-hand-...d-blender.aspx

Makes the resultant beverage all that much better!

Bruce

[techfan]

Why not kick it up a notch? Don't waste time and effort with a hand crank blender, get a 24 CC 2 stroke, 2-1/4 hp GAS operated blender by Tailgater! Amazon.com: Tailgator Gas-Powered Blender: Kitchen & Dining

One of you clever folks could probably even figure out how to use this to charge those batteries and make margaritas all at the same time. Yep, bet you didn't know you needed one of these.

[hotfishtacos]

Originally Posted by Jim Bennett

...We do take a small gen set sometimes though...

Jim, I am shocked!