Electrical questions about boondocking in Caravel

[Stefrobrts]

I need some electrical learnin' from you folks!

My Caravel has one RV battery and an Intellipower with Charge Wizard. All the lights in the trailer are 12v. The Fridge is 3-way but works best on propane so that is how we use it - I don't know if it uses any 12v power when on propane. The furnace is a modern furnace like what is found in new Bambi's, it needs 12v to run the fan. WH is original propane. I have no battery monitoring system.

My goal is to be able to last a week unplugged. Right now I have run out of juice after a 3 day weekend.

So I am switching all the interior lights to LEDs. I probably should add a battery monitoring system. I would like to figure out how much power the furnace uses while running. We usually just run it at night to keep the chill off.

I'm trying to determine if I could do something simple to make it a full week, like adding another battery to the system. There is room to add another battery if I go that way. I don't know if there would then be issues with my Intellipower charging both.

Advice from those more knowledgeable in electrical matters would be appreciated.

[adonh]

You can try Camper Clinic in Buda TX http://www.camperclinic2.com/New-RVs...-xNewInventory

[Stefrobrts]

Well, I need to understand the system a bit better before I start plunking down money on a battery monitor and stuff. I am getting the LEDs ordered from Dan (as soon as I figure out how to access the bathroom cabinet), so I'll get that ball rolling.

[Lily&Me]

Your system sounds similar to mine.

What I do......use the interior lights as little as possible.

When it is dark enough that I need light to read, I light a small candle and use one of those tiny, clip on lights.

They are very bright, and the batteries last a very long time.

Still, I could not go a week. By 4 days or so, I need to run the engine for awhile to charge things, or run the generator.


Good luck!


Maggie

[Al and Missy]

Here is what I came up with when I was considering solar for my trailer.

Refrigerator - 0.2A all the time, even on propane = 24hours * 100% * 0.2 A = 4.8 Ah
Furnace - 7.6A when running - figure 30% duty cycle (more if colder) when its on - 7.6 A * 30% * 8 = 18.24 Ah
Water pump - 7.5 A for an hour at each meal but 10% duty cycle - 7.5A * 10% * 3 hours = 2.25 Ah
Water heater (if electric ignition) - 1.5 A at 100% for 3 hours - 1.5A * 100% * * 3 hours = 4.5 Ah
Incandescent Lights - 1.4 A per bulb (based on the bulbs that were in my trailer), say an average of three bulbs on for a total of 4 hours - 1.4A * 3 bulbs * 4 hours = 16.8 Ah

This scenario totals 46.59 Ah per day. It probably doesn't match yours, but you can see from the example how to do it, and how you might be able to reduce power consumption. For example, LED bulbs will draw only around 0.3 A, v. 1.4 for your current incandescents.

As you can see, lighting is second only to the furnace in power consumption.

For optimum battery life you should not discharge a battery below 50% of capacity. Some say even less discharge.

Group 24 Battery = 70 Ah*50 = 35 Ah or less than one day
Group 27 Battery = 108 Ah * 50% = 54 Ah or just over 1 day

Assuming you are fully discharging your batteries, the Group 24 would last less about a day and a half and the Group 27 just over two days.

Adding another battery will approximately double your capacity, but if your existing battery is old you should probably replace it if you are going to wire them in parallel. If you are going to put in a switch to go from one to the other, then you can keep the old battery with no penalty.

Hope this gives you some insight.

Al

[polarlyse]

LED's will help a lot but keep in mind that the Refrig will use a little of your 12v power even when on propane. We have 2 batteries and being stingy with the power and water pump but with the refrig on propane the whole time we've gone 4 days on batteries. We were moving at that point so don't know how much longer we could have lasted but so far that has been our upper limit. That was with NEW batteries. They are on their 4th year now so may not last as well.

[mojo]

Best bet...two batteries and a generator for 3 or more days unhooked. LED lights are a plus, and running the furnace at a low temp at night with a sleeping bag on top helps. You don't want to run the batteries down past 50% so topping off with a genny is a must and you can run in conjunction with the furnace in the AM while the trailer warms up.

[Stefrobrts]

Originally Posted by Al and Missy

Here is what I came up with when I was considering solar for my trailer.

Refrigerator - 0.2A all the time, even on propane = 24hours * 100% * 0.2 A = 4.8 Ah
Furnace - 7.6A when running - figure 30% duty cycle (more if colder) when its on - 7.6 A * 30% * 8 = 18.24 Ah
Water pump - 7.5 A for an hour at each meal but 10% duty cycle - 7.5A * 10% * 3 hours = 2.25 Ah
Water heater (if electric ignition) - 1.5 A at 100% for 3 hours - 1.5A * 100% * * 3 hours = 4.5 Ah
Incandescent Lights - 1.4 A per bulb (based on the bulbs that were in my trailer), say an average of three bulbs on for a total of 4 hours - 1.4A * 3 bulbs * 4 hours = 16.8 Ah

That is very helpful. How were you able to determine how many amps each appliance was using?

[mandolindave]

I think? that the furnace fan motor uses the most electricity because it is used longer than the water pump.

I think the thing that limits most boon dockers is water supply and filled waste tanks.

[Jim Flower]

You are actually pretty modest in your electrical requirements, about the same as my son with his 67 20' GT. He has a really great 1 panel solar kit from AM Solar. 2 group 27 batteries. LED lights. Boondocks indefinitely in the summer in northern Alberta. 18 hours of daylight. He installed the kit himself since it comes so well prepared. It all simply provides complete independence except for the usual water and waste caveats. Jim


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[Stefrobrts]

Since we'll be in a dry campground I plan to use the 'facilities' as much as possible to avoid filling up the black tank, and the grey tank (blue boy) can always be put in the car and carried down to the dumpstation mid week. We have like 35g of water on board, we have NEVER run out of water - everything else runs out first

I'll check out the solar kits. Using sunlight to recharge sounds great, but we also try to get shady spots so that might work against us.

[Jim Flower]

It's interesting on how Solar might change your preferred habitat. Depending on the length of your stay, you view a potential site differently. Does it have enough sun? Will the shady bits hurt production at the best time of day? Of course, increasing the size of the system decreases the number of things you have to be concerned about. I have found that the only thing I worry about is having enough juice in the morning so that the electric coffee pot comes on at the preset time and makes a full pot of coffee. Jim


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[Al and Missy]

Originally Posted by Stefrobrts

That is very helpful. How were you able to determine how many amps each appliance was using?

Stephanie,

I used a combination of the manuals that the PO left in my trailer and data from internet searches on my appliances. If your water heater has a pilot it may use less electricity, if any at all. The furnace data is probably good, your blower may be smaller. If you don't have manuals, the data may be on a label in/on the appliance somewhere.

Al

[Stefrobrts]

Yes, my WH has a pilot, it is the original WH. I have a battery powered ignitor on it, so it does not use 12v at all.

The furnace and fridge are both new, I should have the manuals for them. I think the only other device that is wired into 12v is the LP detector, which obviously runs all the time. And the water pump. I can look up what kind it is and see if I can get an estimate, but it is quite old.

Thanks for the tips, I'll see what I can find. Luckily it's a very simple trailer!

[Foiled Again]

How to Recharge your batteries. Solar technology is improving almost daily, however it has lots of caveats. So I wasn't all that impressed with a single factory panel on my almost new 2012 EB. Having had it for nearly 2 years now, I admit it's almost put the old Honda 1000 generator out of business. The generator came with two wires to directly charge my batteries. I've never used them - simply because it's really easy to overcharge batteries and "kaboom" is one possible side effect. I'd always had a battery charger that would go into trickle mode as the batteries became near fully charged. So I used the 1000 to run the battery charger, or a hair dryer, an induction burner, or recharge the batteries on my drill or vacuum, etc. (I've lent it out to run a CPAP machine all night too.) A Honda 1000 is minimal power... and minimal weight/noise. Don't even THINK about running your A/C with one, but recharging batteries and boondocking til the waste tanks overflow, great!

Solar is great if (1) the sun shines or (2) you are parked in full sun.

A little generator will run as long as you have gas and can pull the starter cable. (Don't make the mistake of trying to siphon gas from your truck's tank to fuel the generator, most modern tanks have anti-siphon technology to keep people from stealing gas.) If I know I'll need the generator I fill it's tank and a 3 gallon can. It's a good idea to use fuel without ethanol too - or use Sta-Bil to keep the gas from getting water in it - or just run the tank dry when you use the generator.

[D Bishop]

In my 65 Caravel I use a 14 Watt self regulating solar panel and place it on the sunny side of the trailer. I installed a plug to go to the battery. I have used this system for years and have never run out of power. We nearly always Boondock and seldom have shore power. I leave the panel hooked up and in a sunny window to keep the battery charged all year.

Don B

[idroba]

Your Caravel probably has minimal electrical needs. If you have an original type refrigerator, there will be no power draw at all. If a replacement, it might average half an amp an hour. Your furnace will draw about 4 amps, the 7 amp load mentioned in one post would be for a much larger furnace than you have.

The biggest change you can make is with the incandescent lighting. Change it to LED and you will cut your power draw from lighting by 80% or more.

Add a second battery, or replace both with a pair of deep cycle golf cart types. That will increase you battery to double to triple what you have now.

Consider a modest solar system. It also will do wonders to your trailer electrical system.

[idroba]

Oh, if you ever plan a trip to Idaho, let me know. I have a place for you to stay and will be glad to do a complete electrical evaluation of your Caravel for you. I love to do electrical things and can monitor and show you what uses power and how much.

[Jim Foster]

I put two 6v Trojan batteries and. 55w solar panel on our '65 caravel. I carry a Honda 2000i generator to run the microwave and espresso maker. Started off with no solar and no generator.

Bite the bullet and be done with it.


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[Stefrobrts]

Originally Posted by idroba

Oh, if you ever plan a trip to Idaho, let me know. I have a place for you to stay and will be glad to do a complete electrical evaluation of your Caravel for you. I love to do electrical things and can monitor and show you what uses power and how much.

I hope I can take you up on that someday - There are a lot of things to see in Idaho on my must-do list!