[Repost]

What do we do?

I recenty purchased this truck/cabover. I have taken it out twice, four days each. Killed the truck battery both times. I don't have another trip planned for a few weeks and I'd like to reconfigure the electrical on it.

Here is what needs to be powered now.

4 12v dome lights
1 12v water pump for the sink
1 6,000 BTU Furnace - I'm not real familiar with these for power consumption if any is needed
1 12v,110v, propane 3 way fridge/freezer.

As it currently stands it seems you need to have the key in the run position for the lights and furnace to turn on. Fridge is all propane once parked.

I'd like to isolate the truck from the camper completely. Next few trips will be by myself so no jump starts possible.

There is a battery tucked away under one of the seats in the camper, not sure of it's condition or capacity. I can add whatever is needed battery wise.

In the future i'd like to also add the following items:

Outdoor shower
Stereo (probably just a 4 speaker car system)
110v access for laptop, maybe a dvd player or something for the rainy days
maybe a roof top AC (depends on weight as it's a pop up)
Some bright out door lights

So here are the questions and options.

batteries - How many, what kind.
Solar?
Generator?
Some sort of battery life gauge?
Kill switches?
12v to 110v (invertor/convertor)
what else?


I haven't seen much on remote location electrical on here and figured it'd be a good topic. So let's here what you all are doing?


Jay
:beer:

 

[Elwenil]

It sounds to me like the system is currently designed so that the engine is running when these items are to be used. There is no other reason to wire it up to the run circuit and if there is only one battery for the truck, it would be impossible to expect it to keep up with any use for long. About your only real option to run all the accessoies you want to run would be a generator of some sort if there is no plug in power available.

 

[Repost]

You are right. That's what needs to change. I don't want to run the truck every couple hours to maintain a charge. I want the truck to be just truck power and the camper to have it's own rechargeable system.

 

[hadfield4wd]

How about some kind of solar recharging thing?

 

[crashnzuk]

Since there is a battery in the camper, it must not be any good. Start there. The other thing to look at is there must be some kind of isolater that isn't working. You will need to figure out how it's wired and why it isn't working. You could try www.rv.net , they have a really good truck camper forum.
Travis..

 

[czechsix]

Get some LED lights in the domes, that'll help. For the furnace, look at the data plate, it should give you numbers so you can figure out draw. Or call the manufacturer. Same with the fridge/freezer.

Sounds to me like someone screwed up when they installed it - no way you should have to have key on to get power to the thing. I think they cheaped out on the install, lol.

So, you need a dedicated system, or at the least one of the battery draw down safeties - the ones that'll stop the draw to your accessories once you get close to the critical point, letting you still start the truck.

I'd run dual deep cycle batts, just for the camper. Tie them into the charging system with an isolator, and if you plan on sitting still for quite a while, size a solar system for it. Shouldn't be too expensive to set up, some panels, mounts, charge controller, and maybe an inverter. If you want to get more backup, add in a small genny.

Basically, start with what you need to power now, and if you've got the money, figure what you want to have in the future and size the system for that now.

 

[Repost]

ok, here are the ratings on the equipment

Dometic RM2201 Fridge
12v 8 amp
110v .85 AMP

Hydro Flame Furnace
16,000 BTU
12v 2.9 amp 34.8 watts

Jabsco Water Pump model 42510-0000
12v 1.6 amp

Interstate Megatron
Marine-RV Deep Cycle
SRM-24
550 CCA
690 MCA

that's all I have time for now. I'll add more later

 

[Elwenil]

Ok, I may have misunderstood the initial post. Are you saying that there is a battery in the camper itself that is not the battery that the engine runs on? If that is the case, then that battery is probably dead and the only way you are running the electronics in the camper is through the charging circuit with the key on that normally charges the battery while the vehicle is travelling. It's very possible that everything is working correctly other than the defective battery. If it held a charge, you could turn off the engine, which would isolate the truck's battery from the camper and you could run off the camper battery until it died. With the camper battery dead, the lights will only work off the charge circuit to the truck's electrical system.

 

[Repost]

Ok, I may have misunderstood the initial post. Are you saying that there is a battery in the camper itself that is not the battery that the engine runs on? If that is the case, then that battery is probably dead and the only way you are running the electronics in the camper is through the charging circuit with the key on that normally charges the battery while the vehicle is travelling. It's very possible that everything is working correctly other than the defective battery. If it held a charge, you could turn off the engine, which would isolate the truck's battery from the camper and you could run off the camper battery until it died. With the camper battery dead, the lights will only work off the charge circuit to the truck's electrical system.

That is what i am saying. I still think it will be insufficient for heavy use for several days. Like I said I plan on adding alot of things as well.

I want to totally redo the electrical system in this thing. I want big power for the "extras". I want a good rechargeing system with little to no use of a generator. I know I need a generator, in case, so what kind?

I know alot about automotive electronics, a very little bit about resedential and ZERO about combining the two.

 

[ken white]

That is what i am saying. I still think it will be insufficient for heavy use for several days. Like I said I plan on adding alot of things as well.

I want to totally redo the electrical system in this thing. I want big power for the "extras". I want a good rechargeing system with little to no use of a generator. I know I need a generator, in case, so what kind?

I know alot about automotive electronics, a very little bit about resedential and ZERO about combining the two.

I use a Honda EU2000i for my camper - weighs 46 lbs and runs a much bigger load than you have.

I purchased it here: http://www.wisesales.com/

Best shipped price anywhere.

You could try and size batteries and solar panels but I really doubt you want to carry the extra weight, lose storage space, and want to play with panel orientation...

ken

 

[Repost]

I was just looking at that one. How is it for noise?

 

[ken white]

I was just looking at that one. How is it for noise?

Very quiet since it uses inverter technology. Inverter technology varies the engine rpm with load so is very quiet when lightly loaded and a little louder when fully loaded.

 

[the_experience3006]

It's all about battery reserve capacity management. Your little Group 24 deep cycle is outgunned from all flanks with what you want to do.

First and foremost I would recommend you calculate how many amp hours of capacity you will need. This is by no means a precise amount because of various factors, namely Peukert's Law which shows that reserve capacity of a battery is not a linear thing based on draw.

Anyway...amp hours are just that...amps times hours. If you have a device that uses 5 amps for one hour you need 5 Ah capacity. If you have a device that draws 1 amp and you need it to run for 5 hours you still need 5 amp hours of capacity. Converting to amp hours will put everything in common units we can use.

Figure out the maximum number of amp hours you are going to need. You will have to do some homework and figure out how long per hour the fridge and furnace are actually drawing current. Err on the high side.

Ok, once you have calculated this out I think you will find it is a staggering amount of power when you come to find out that your Group 24 is only good for 105 amp hours on its best day. Not only that, but to get that full 105 amp hours you will be discharging the battery damagingly low.

So...we have the total number of amp hours you need. Now it's time to make the number realistic and better for our batteries. Double it or even triple it. Yep, you heard me right. Double or triple that number. This will help compensate for that Peukert bastard and will leave some reserve capacity in the batteries for an emergency as well as extending their life cycle.

You do not want to drain a deep cycle battery to more than 50% of its capacity...ever. Don't let someone tell you you need to drain it fully and then recharge it to avoid a memory. This is completely false for the lead acid type battery. They will last the longest being kept at a strong resting voltage in a cold place and not being used at all.

Fully charged the battery will read 12.6 volts. Fully discharged it will read 11.8. Discharged to the rated capacity the battery manufacturer gives you it will be closer to 10.2 volts. That is terribly destructive. You don't want battery voltage to drop below 12.2 volts.

I bet you've discovered that you need an incredible amount of reserve capacity. You may well need to compromise and run the truck to try and recharge the batteries. It will never fully charge the batteries, but will give you more capacity. If the alternator is turned for an hour and it pushes 60 amps to the batteries you will have recovered 60 amp hours to use. I hope that makes sense.

There is far FAR FARRRR more to it than that, but do that much. I will give you my recommendation right now and that is that you get a pair of 6 volt golf cart batteries. Wired in series these will give you about 225 amp hours of capacity (100-120 usable) and are incredibly durable, tolerant, and long lasting. The disadvantage is they are big, need to be purchased in pairs, and will require occasional maintenance.

Another option is to get an 8D deep cycle battery. This is the BCI group size you would find in a load or a bus for example. They have a pretty incredible reserve capacity as well and are good tough batteries.

I could write on and on, but I'm not going to unless you need more information. Post up and questions you might have and I will try to help.

 

[Chainlink]

experience3006 that was super easy to understand, if no one else finds that useful I would be surprised.

I do have a question though, I understand solar panels are weak in comparison but wouldnt they help? I figure if they spent the whole day charging wouldnt a frig and such not running constant would still let the batteries charge. Of course I mean this in a supplemental way, so that a generator needed could be smaller duty?

 

[Elwenil]

If I did my math right the largest solar system I found readily was a 440 watt system for $2,600 only puts out about 36.7 amps at 12v. A very small refrigerator, I used the Norcold N260 as an example, pulls 11.7 amps at 12V. Not a very cost effective or efficient system.

 

[the_experience3006]

I do have a question though, I understand solar panels are weak in comparison but wouldnt they help? I figure if they spent the whole day charging wouldnt a frig and such not running constant would still let the batteries charge. Of course I mean this in a supplemental way, so that a generator needed could be smaller duty?

See below. They are helpful, but for the money I'd rather just run a nice genset like a Honda EU2000.

If I did my math right the largest solar system I found readily was a 440 watt system for $2,600 only puts out about 36.7 amps at 12v. A very small refrigerator, I used the Norcold N260 as an example, pulls 11.7 amps at 12V. Not a very cost effective or efficient system.

Exactly. I actually considered using the Harbor Freight solar system for my bus. $200 on sale for a 45 watt panel is a pretty stellar deal. There are not than many photovoltaic cell manufacturers out there so even the Harbor Freight ones are likely made by a known brand. Then I did the math.

The 45 watts is maximum potential. We will first of all assume that it is at a voltage great enough such that it can charge the batteries. Let's call that 13.5 as this is adequate voltage to charge a 12 volt battery. That 45 watts is also assuming perfect conditions which means cold conditions with direct sunlight being tracked perfectly by the panel. I'm going to be VERY optimistic and say that 30 watts is a reasonable figure for output you might actually see.

30 watts divided by 13.5 volts=2.2 amps

Now let's assume we get 12 solid hours of charging time (yeah right).

12 hours * 2.2 amps= 26.4 amp hours

Ignoring the Peukert bastard again we can assume that the fridge can run constantly for about 3 hours on that amount of power.

So...being VERY lenient and expecting the best I still think that the solar panel would fail to keep up with even just one component of the system.



I'm not opposed to solar and if you spend enough to get some serious wattage you might be able to make it work, especially if you understand that after 4 days your batteries might be toast even with the solar assistance. But you need to understand that part of that STILL requires a good, solid battery bank. That is the foundation of the whole system. What good is 10 gallons of free gas (energy like solar) if you only have a 5 gallon can to store it in?

As far as generators I don't think you can go wrong with a Honda EU2000i. They are incredibly fuel efficient, modular, offer clean power, and are quiet. The other models in the EU series offer similar benefits in different size packages. The EN2500 is also a good generator. It is not as quiet or quiet as fuel efficient or compact as the EU series, but is leaps and bounds better than a Coleman with a Briggs and Stratton chugging away.

What do I use? Well...I try and plug in whenever possible! However, I have a large bettery bank for the bus. I can throw a reasonable charge at the batteries using the bus engine due to the 130 amp Leese Neville alternator. That's a real 130 amp alternator, not a GM-130 amp-when-struck-by-lightning alternator. I also just built a truly *******/hillbilly genset for myself. Using a 1 wire GM alternator, a queen size bedframe worth of angle iron, and the front half of an old 12 horse Briggs and Stratton Crapsman lawn tractor I built one of the biggest, ugliest 1000 watt generators you will ever find. However, because of the pulley ratio and power of the engine I can spin the alternator to peak output just above engine idle. That means low fuel consumption and reasonable volume levels. The alternator is capable of keeping up with my electrical needs as I go. If I turn some stuff off I can actually put a charge to the battery bank.

But what's the biggest secret? Energy conservation! Alter your lifestyle. All my lighting is fluorescent. Anything that makes heat burns fuel of some type, not electricity. I use good coolers with ice for beverages so I can just use a small, tightly packed dorm fridge for things that are more temperature critical. Turn lights off when you're not using them. Turn the radio down or use headphones to reduce its draw. Charge the batteries at every available opportunity. I have gone so far as to plug in my bus to run the 120 volt loads and to top off the batteries at a Wal-Mart while I shopped. You'd be surprised how many of those light poles have outlets on them...

It takes practice and it isn't easy to live off the grid, but once you acclimate and figure it out it isn't that bad at all. I can go 36 hours off the grid without charging my batteries in any way shape or form running two dorm fridges, a TV, PS2, lights, stereo, etc. It's all about management.

 

[ken white]

The main issues with any 12VDC energy systems in a truck camper is the cabling must be physically large to handle the higher DC currents for a given load, battery storage space and weight capacity isn't always available, and a much larger charge controller is needed for more cells. While I don't really like carrying extra gas, the little honda runs all of my 120VAC appliances while keeping my single battery charged for when I want to run without the generator.

 

[Repost]

good info 3006!!:beer:

I found a worksheet online for appliance consumption.

I kind of guessed randomly.

lights- 8 amps total - 16 amp hours total.

tv 4.4AH
stereo 8AH
Heater 60AH
WaterPump 15 AH
Refrig 50AH
Laptop 16AH

So per day I'm guessing about 170 AH on a cold day worst case scenario.

Sound reasonable? I'm sure that not everyday I'll have the radio going all day or use the Laptop as much. I want to be able to though.

I'm taking a wild guess on battery selection with this one
http://www.trojanbattery.com/Products/T-1456V.aspx

run two of those? and a generator back up?

I also have access to good condition Optima RedTops for super cheap if that's an option. I've heard these Trojans are the way to go though.

 

[the_experience3006]

Trojan T-145s :smokin: Good choice

I'm going to be gone for almost a week here (living off batteries ) but you're on the right track. Here is some excellent reading for you. He and I agree on most stuff.

Poop Sheets

 

[Repost]

Trojan T-145s :smokin: Good choice

I'm going to be gone for almost a week here (living off batteries ) but you're on the right track. Here is some excellent reading for you. He and I agree on most stuff.

Poop Sheets

Thanks you sir, enjoy your trip.