Questions on Setting up an auxillary power system in my FWC

[CJ8Rockcrawler]

I'm working on "tweaking" the power system in my FWC. I will be adding a DC to AC Inverter as well as a few other odds and ends. I've been using the spreadsheet from the wander the west site to calculate my total amp draw. It looks like I will have 2 separate systems, one in the truck and one in the camper.

From the factory, the Dodge comes with dual batteries that from what I can tell are traditional starting batteries with some reserve capacity (to run the grid warmers for the Cummins I assume). It looks like I have a total of 375 Amp hours between the 2 if my calculations are correct. Someone that may know better can tell me if my calculations are sounds. Each battery is rated at 150 reserve minutes, but do not list amp hours. From what I found here.
300 reserve minutes equals about 375 amp hours.

I only need about 32 amp hours/day for what I want to run off of the truck's factory system so I theoretically can run these accessories for 5 days w/o dropping below 50%. Although, I'm sure I don't want to run these batteries down that far since they also must start the truck... I don't see any reason that 2 or 3 days w/o moving would be an issue though.

Now for the camper system, there is currently 1 deep cycle battery installed that is charged off of the factory system, but has an isolator in place to disconnect it from the truck when the truck is shut off. I need to research the battery that is in there (it was installed by the previous owner) to determine its amp hour capacity. I'm guessing it is somewhere in the 105 to 110 range though and my daily demand is ~110 amp hours. So I have about a half day's capacity with the current single battery to keep it above 50%.

So... the million dollar question... What is the most logical step to keep everything running for 2 to 3 days?

Add another Deep cycle battery or two?
Generator?
Solar?
Some combination?

Have at it ladies and gents... I look forward to your insight.

Kyle

 

[SunMan]

Kyle,
What all will you be running power wise?

Just to give you something to gauge off of I'm runnning an Optima Blue Top (with isolator system) in my Hawk and have ran the interior lights (fluorescent), fantastic fan, rear flood lights for lengthy stretches of time in the evenings, used the water pump, listened to my iPod via a plug in dock for many, many hours per day, and never even phased the battery over a 3 day period. I know that is not much equipment compared to others, but maybe it will give you an idea. FWIW I was very surprised the flood lights didn't drain it more.

 

[kbennett2000]

Kyle - What I always disliked about the idea of a generator was having to carry yet another type of fuel. A few weeks ago I came across a company that sells propane conversion kits for most popular generator models. Not terribly expensive and it gets you back down to just two fuel types, if that's a concern.

I don't own one of these kits (or a generator) so I can't comment on the performance...

http://www.propane-generators.com/

 

[chnlisle]

Kyle I too am running a Optima Blue top as a a house batt. I ran Fantastic Fan the other day for 12 hours and still had over 50% of the batt power left according to the idiot lights. I would be very interested in what you come up with. If just adding another batt will insure a week of power that would be the easiest solution. Of course we could alway just start the truck for an hour.

I think I need to turn the lights and fan on and check the power usage.

 

[Sam]

Do a search, there is lot's of info here on this topic, also search the net. I use dual 6 volt Trojan AGM batteries based on what I read on various internet sites and I have been thrilled with their performance. I have had very bad results with Optima Red Top in my truck, but never tried the Blue or Yellow for camper use.

 

[pvstoy]

Do a search, there is lot's of info here on this topic, also search the net. I use dual 6 volt Trojan AGM batteries based on what I read on various internet sites and I have been thrilled with their performance. I have had very bad results with Optima Red Top in my truck, but never tried the Blue or Yellow for camper use.

Hi Sam,

Sorry you had bad luck with the red top in the past. 10 years ago I put a Blue Top deep cycle and a Blue Top starting battery in the Toyota. I have not had a stich of problems as of yet. Wonder how much longer they will last?

At the time the deep cycle Blue Top was the same as a Yellow Top and the Blue Top starting was the same as the Red Top. Just different wire mounting. Then the Blue Top deep cycle was made a little better than the Yellow Top.

As what they are now Have not followed them since thier patten was up and other likes came out. I even heard that new owners took them over.

When mine die I should find out what I should replaced them with. Wonder if the new Blue Tops will last 10 plus years???

I was thinking of two deep cycle batterys together with a nice solar set up would be the ticket. But I was thinking of long winter trips with short cloudy days if solar would keep up if you were parked for a week. I think it would?

 

[Sam]

Pvstoy,

I know I'm the exception as lots of people have had great luck with the Optimas. I believe Optima was purchased in 2003 by Johnson Controls (80%) and Bosch (20%)

 

[chnlisle]

Pat I think if you have the time and money solar is a great mod especially if you are stationary for weeks at a time. Since we dont run anything other than our camper lights soon to be led's, the fan and a lap top for music I think an additional batt would solve my problem and save a lot of dough.

I dont like all the additional weight on the roof and the wind drag. Diesel wont be getting any cheaper any time soon.

I thought about the new Yamaha generator that uses propane and gas but as I said in a previous post I have a 350hp generator under the hood. I can always start the engine.

I think I'll go out and turn the fan a camper lights on and see how much juice they use over 12 hours.

 

[the fisherman]

Power Ah Plenty

You can find possible solution in my closet.

 

[chnlisle]

I turned on the fan and lights with the batt half charged according to the idiot lights so we'll see how long it lasts. I forgot to mention that I do have a Swampy and it will run all night when we're out in the summer. It only uses 1.5 amp hours.

Ok Salty, Why do I need an isolator or 2 batt switch if I run 2 batts in series. The charging system is set up to only work when the truck is running. Wont both batts discharge and charge at the same rate without the switch?

 

[b team]

Some combo should work for most conditions.

 

[chnlisle]

When I went out to turn off the interior lights and fan they had been on for 8 hours on a half charge and still running. I'm guessing that would last me 4 to 5 days in camp on a full charge. I guess it wouldn't hurt to put another batt in. I'd still like to know why I would need a battery switch or isolater.

 

[CJ8Rockcrawler]

Jay,

Are you asking why to isolate the system from the truck or why you would isolate the 2 camper batteries from each other?

Isolating the truck batteries makes sense to me so that even if you use up all the power in the camper either purposely or by mistake leaving something on inadvertently, you can still start the truck to head out/recharge.

Isolating the camper batteries from each other... the only thing I can think of is if one goes bad you can isolate and work off the other battery with out it discharging into the "bad" battery. Perhaps it also allows you to read the voltage still remaining independently on the gauge. Got me on any other reasons though!

Kyle

 

[chnlisle]

kyle you make a good point.

The truck is already isolated from the house batts by virtue of the solenoid. The only reason I can think of to isolate them from each other is if you can't get a full charge on both if one has discharged more than the other. Then you could charge them seperately. Which is what I think an isolator does. It makes it possible to charge both completely. I seem to remember someone telling me that without some kind of way to charge them individually they will only charge to the level of the one least discharged. Does that make any sense? But I really don't know. I feel like an idiot here. After owning as many boats as I have with dual batt systems you'd think I would know this.

HELP!!!!!

 

[the fisherman]

Mr. Pueblo

Normally the selector switch is used on a boat to isolate the starting battery from what is called the house battery, electronics, lights etc. also to combine to weak batterys for a start. In a series wired system a weak battery will draw the other one down much faster. The reason I used one is when I went through my camper I tossed the cheapo fuse block in favor of circut breakers, also in the closet, hard to get a pic. so now the entire elec. is in the closet. The switch is now my master power on/off. Also if I want a quick charge off my gen. I can isolate that battery.

 

[chnlisle]

So Salty if I install another battery and wire the 2 of them through a battery switch I can then use one or both at a time and charge one or both at a time?

Also as I recall in the boat when we were under power I had the switch on "BOTH" to charge them. Thats when I was told that they would only charge to the limit of the least discharged battery. Is that correct?

 

[the fisherman]

I Should Be Mowin' The Lawn

MR. PUEBLO: I did not mention that my camper is for the most part independent from the truck, I can take a charge from the truck or run the refer. while on the road, the rest of the time it's solar powered, 50/50 or 90/10 controller, with cond. meter, that way I can moniter the cond. of the batteries and use them to their best advantage, thus the swtch. Yep with the switch you have a choice #1 or #2, you will probably never use the both position but you can if you have to, Unless you had dual alt. you can only charge one bat. at a time or split the charge in the both pos. I hope this makes sence.

 

[the fisherman]

Kinda Dumb

What I was trying to say was in the both pos. you will be series wired, and you would use the both pos. to charge both bat. while on the road. Or if you want one or the other. Some type of cond. monitor would be helpful. Pueblo, I think there some advantages to a selector, although there is added expence it's probably worth it. Everbody wants what they think will work for them, thats how I ended up with what I have, I know some people think i'm nuts.......they are absoluty right

 

[chnlisle]

As a member of that same fraternity I say WTF. However the switch makes sense. Charge them individually and use them individually. The truck doesn't need them to start as it has two big MF's of its own to start it. I think a dual batt system like what we're talking about will insure plenty of juice on an extended stay somewhere. When one runs out I can just switch to the other. I can charge them seperately as well. Thanks Salty I think you've solved the problem. Now if I can just find a big marine batt switch that was made in the USA.

Kyle If you want to attempt this little project together I'm in. Just a matter of making time for it. Or I can try to do mine and help you with yours or...oh hell we'll work it out.

And people think Salty's nuts...TT tell him what you paid for your FWC.

 

[the fisherman]

Just Ask

BLUE SEAS SYSTEMS, made in Washington, full line of marine grade elec. hardware, not the cheapest, but good quality. If your going to the trouble of a dual batt. set up you need the selector. Check out their site, or West Marine, which is sky high on prices.