Electrical questions

[smileyd]

I am looking for locations on this stuff.

Does your camper have an outlet for rv hook ups?

Explain where? I could kinda guess.

Do you have an inverter/converter in your camper for AC current, recharging battery.....? Where do you keep that.

If you have a gel cell battery where do you keep that and what brand would you recommend? Even a wet cell where do you keep that, expecially since it adds risk? Our camper came with a wet cell and charger in the propane box, as you know we are changing that.

I have been reading the battery thread.

Dorian and I plan on taking care of electrical next. We are looking into a gel cell battery and already got our inverter/converter for AC current. We are starting to rewire, it was kinda sloppy before. As everyone knows we are headed for a long trip and want to be prepared. We would like to know your ideas for storing these items..

Thanks everybody!!!
Angelina

 

[craig333]

Mine came with the converter already in it. I put the optima right by the water tank. The ac outlet is just above the water inlet. So far its never been plugged in, but that should change now that i have a generator.

 

[marty]

Battery

The optima blue top is good as is the interstate glass mat gel only the interstate has lots more amp hours and both of these are safe to put inside the camper as they do not let loose vapors that will hurt you. I do not have a problem with using an acid filled battery as long as it is in a vented to the outside box or even under the camper in a non vented box. But dollar for dollar the interstate is my favorite. If you fuse both positive and negative wires coming from your main battery you will never hurt your truck electrical.

Marty

 

[WarpathEngineering]

marty,

what size fuse would you suggest?

Rick

 

[benburnett]

fuses

We have always used a 30 amp fuse on the battery's. The reason for this is that in theory if you have everything on at once in the camper you can draw close to 30 amps. Depends on the options that you have in the camper.

 

[benburnett]

electrical

I would mount an inverter under the sink against the back wall. Easy location to bring the wires to. Any place will work though, I am just thinking of a spot that is easy to access.

Unless you change the water system, there is no RV hook up for it. When you say RV hook up I assume you mean connecting a water hose directly to the water system from the outside. This requires a pressure on demand type system and you camper was not built for that. You would have to change out all the fittings and faucet if you wanted to put in a pressure system.

As to an RV hook up for electrical, we used to have a 110 plug on the outside of the camper. This was connected to a small one breaker box on the inside of the camper. In turn we came from the breaker box to a 110 plug that was mounted in the small wall at the left end of the counter up top just under the refer top. We would also install a 110 outlet in an accessory cabinet that I made at the far right of the counter on a Grandby model camper.

We used to mount the batteries inside a battery box in the very front corner of the bed on the older trucks. Most trucks today do not have the room to do that. We are currently mounting the batteries under the couch in a battery box in the front right corner of the camper.

Here is a link to the current battery that we use.

http://www.interstatebatteries.com/www_2001/content/products/product_mobility.asp?js=1&mscssid=14R534CQCPA38KRM4BBBDSV0A7NQF698

Scroll down on the page and click on DCS-75BT. That will bring up a PDF of the current battery that we use.

Hope some of this helps.

 

[George]

Marty or Ben,

Since the battery has a lot of capacity, what happens if you run it most of the way down? How much current flows into the camper charge circuit, from the alternator? Could you blow the fuse in that direction? There must be some variation between trucks and alternators. Do you guys have a general idea of how long to recharge the camper battery if it is run down most of the way?

 

[benburnett]

battery charge

Your truck will normally put 14.2 or 14.3 volts to the battery while the truck is running. I have never seen that blow a fuse unless the alternator regulator goes out and over charges the system.

If you do run a battery almost down to nothing, I have found that putting it on a trickle charger for a day or two will usually bring it back to a full charge.

You might give Interstate a call if you have a dealer in your area to explain the dynamics of how that works. I really don't know. Just what I have done for years if I drain a battery.

 

[Sam]

I am working on the same electrical install that you are. I have found that there is a tremendous ammount of information about batteries and related components on the internet and a lot of missconceptions as well. I would strongly recommend you spend some time reading up on the subject, there is a lot to be learned and batteries are a pretty big investment. Since you guys will be on an extended trip in your camper I am sure you want a system that will perform.

Figure out what you want to run and how much those things will draw and then you will know what battery set up to go after. Wet cell batteries are thought to be the longest lasting (with maintenance) and best value but of course there is a venting issue. All batteries vent, but the AGM and Gell vent much less.

You should be looking for the Amp Hour rating on the batteries, this shows how many hours the battery will last at usualy a 20 amp draw. You will find some of the best Amp Hour ratings on 6 volt golf cart batteries, of course this will require that you buy two 6 volt batteries and link them together to get your 12 volts.

I just purchased a pair of 210 amp hour 6 volt AGM batts. from www.ebatteriestogo.com they were not cheap but I plan on using my camper for extended periods away from any other power source and the 420 amp hours these batteries provide should do well for me.

I am still in the learning process on the battery systems but I think that this is an area that will pay off later if you do your homework now.

 

[craig333]

Another nice thing about the agm, gel batteries, is no leak means no corroded terminals to clean. Nice if you put them in a hard to reach spot.

Its not the main reason I have them in my Jeep, but its nice knowing if I wind up upside down, I won't have battery acid leaking all over me.

 

[camelracer]

I'm planning on adding a second Optima blue in parrallel with with the original camper battery and wonder how that will affect the charging current. There's a 30 amp breaker between the truck and camper but the alternator is rated at 120 amps. I assume the internal battery resistance limits the charge current so 2 batteries in parrallel would halve the resistance and double the current. My question is will this exceed the 30 amp system I now have and do I need to upgrade it.

 

[George]

Camelracer,

I'd like to know the answer to that. The old rule was capacity/8, or C/8, where capacity is the amp hours at a 20 hour rate. If your batteries are 80 or 100 amp hours, the old rule would be to charge at about a 25 amp rate for two batteries, but taper toward the end.

The next time your battery is fully discharged, you might take an ammeter and see what the alternator is sending to it. If one battery is getting 30 amps, and you add another, you might have to upgrade something. At least the fuse. Most multimeters won't take 30 amps. I use an aftermarket ammeter that was meant to be mounted in a truck. You might want to wire a fixed ammeter in a handy spot, to get an idea of what is happening. If you really want to use two batteries, you have to keep them charged.

One limit for big charging currents is the size of the wire. The 10 gauge has enough resistance to start knocking down the voltage, at least if you need to deliver 50 amps to your batteries. I think a thousand feet of 10 gauge has one ohm of resistance. If you have 20 feet in the run, that is only .02 ohm, but multiply that by 50 amps and you lose a full volt. So right now the resistance in the line may be about right to limit the charging current.

If you ran another circuit to the second battery, with another 30 amp fuse, that might help. Like I say, a good place to start would be to see how many amps are flowing now, with a discharged battery.

The expensive Concordes are designed for big charge currents. They say 4x capacity, which is a huge current. The Optimas might be, as well. If you want maximum charging, you probably need bigger cables as a minimum, and suitable fuses.

 

[benburnett]

charging

Uh, yep, what George said.

I honestly don't have a clue as to what happens if you hook another battery up. We have never dealt with that before.

George sounds like he knows what he is talking about though. Thanks for the reply on that one.

 

[camelracer]

I realize there are specified charge rates for optimum battery performance but when you're charging off the alternater you don't have much control over the current. I think I'll take your advise and monitor the current next time the battery is down. I've got an old amp guage I can use. Thanks for the info.

 

[b team]

I use a 1000W xantrex x power inverter. I use it to run tv, laptop, charge electronic device batteries, and Christmas lights.

It is mounted under the bench seat and permantly wired to a built in inverter 110V system of power outlets:

I'm making changes to this though.

 

[benburnett]

2 6 volt batteries

A customer just sent me this drawing on 6 volt batteries. I believe it was Sam that stated he had purchased two 6 volts at 210 amp hours and is looking at 420 amp hours by hooking them together.

I am assuming here that Sam plans on hooking them up for 12 volt for the camper. If that is true, then the amp hours according to the drawing would still be at 210 for 12 volts. If the batteries were hooked in parallel, then they would provide 6 volts at 420 amp hours.

My knowledge on electrical is limited, so if this is not correct, someone please correct me.

 

[b team]

You got it ben.

voltage will double but amps will stay the same in the series photo.

 

[Sam]

Ben,

Thanks for pointing this out, I was sureley mistaken thinking that I would get double the amp hours.