Expo Trailer Electrical System Question

Phxdsrtrat

Observer
Thanks for all the help guys. I think im going to make it easier on myself and do this system in phases. I plan on doing more off the grid camping than campsites, so I want to be able to charge my battery while driving and not require any shore power. This would mean that I would more than likely have to connect my inverter to the jeep. I can incorporate a shore charger in the near future. This would simplify my set up and installation.

Can anyone recommend a good "bang for the buck" deep cell?
I plan on using 10ga from my jeep battery to the trailer for the battery charger. What gauge would you use to run from the battery to my fuse panel?
How new is your jeep? An issue I (and many others) have run into charging a deep cycle battery only from a newer model tow vehicle is that modern vehicles use a multi-stage charging scheme. This lengthens battery life and apparently improves mileage by reducing the draw on the alternator (this last part I'm skeptical of). The fact is, between the voltage drop from the wire run and that your vehicle may be reducing the charge voltage because it is only accounting for the vehicle battery you may not get a high enough voltage to charge your deep cycle battery in the trailer fully. For me I rely on battery operated everything so having a fully charged battery when I arrive at my destination was important.

There are solutions to this issue but they aren't cheap. For example, I installed a Redarc BCDC 1225 DC to DC battery charger in my trailer. This will step up the voltage so that you get proper multi-stage charging and management of your deep cycle battery. This particular unit can also attach to a solar array for solar charging acting as the solar charge controller.

A 10 gauge wire for charging should be fine. A Jeep is a short vehicle so the wire run length won't play into voltage drop as much as it would on a longer vehicle or a trailer with the battery mounted in the rear.

Now, if you want to keep things really simple and you will have less than 4 fused circuits at less than 30 amps each I highly recommend this. Blue Sea Systems Battery Terminal Block. You should inline fuse the charge wire as close to the Jeep's battery as possible and run that directly to the post of your trailer battery. The fuse block would then also attach right at the battery post providing fused circuits as close to the battery as possible for your accessories.

-Curtiss
 
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Yea my Jeep is a 2011. I understand what you are saying. i like the simplicity of that unit as I plan on adding solar next year. However I am doing this trailer on a budget and its tight around christmas so I will have to look for an alternative. Maybe just a shore charger and a decent inverter on the jeep to top it off.
 

Phxdsrtrat

Observer
Yea my Jeep is a 2011. I understand what you are saying. i like the simplicity of that unit as I plan on adding solar next year. However I am doing this trailer on a budget and its tight around christmas so I will have to look for an alternative. Maybe just a shore charger and a decent inverter on the jeep to top it off.
An inexpensive battery charger that you can use at home before the trip and then top off through an inverter is definitely a plan. Just make sure your charger isn't bigger than the inverter and you're good to go.

Looks like I edited my post after you replied. You might want to go back and check out the addition I made for keeping the 12VDC setup simple. It's stlll worth running the charge line to maintain the battery while traveling and the Blue Seas battery fuse block is a great, simple solution for the electrical if it fits your needs.

-Curtiss
 
Hey guys I really need some help sizing my battery charger and inverter. I have a 12v 125ah battery. Im looking to shore charge it at home and charge by inverter on my jeep while driving. What would be a good charger for this setup?
 

Bullseye240

Adventurer
Hey guys I really need some help sizing my battery charger and inverter. I have a 12v 125ah battery. Im looking to shore charge it at home and charge by inverter on my jeep while driving. What would be a good charger for this setup?
Charging the battery at home can be handled by any of the available charger/maintainers but why would you want to use the inverter to charge the trailer batter when towing? There is no reason to go from 12vdc to 120vac only to convert it back to 12vdc at the other end. A 7 pin trailer connector has the extra connection point to provide ample charge to recharge and maintain a charge while towing.
7-pin-trailer-plug-wiring-diagram.jpg
 
With a deep cycle battery though you ideally want a DC-DC charger inline with the trailer wiring to charge the battery properly, a straight connection will work in a pinch but it isn't great for deep cycle batteries.
 

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Bullseye240

Adventurer
One good reason for converting is overcome resistance in a potentially high current long distance 12V circuit. Sort of 'poor-mans' work around -vs- using an expensive dc to dc charger.Yay for finding high quality "RV grade" electrical connectors !
I've seen, used and repaired tractor trailers with lift gates mounted on them and not one ever had anything other than a 12 volt source running from the front of the truck to the rear trailer mounted battery/batteries. Again there is no reason to convert 12vdc to 120vac only to convert back to 12vdc at the other end. The load imposed by all the conversions will ruin an alternator in short order. Always had a hell of a time trying to explain to truck drivers that the reason they kept frying alternators was all the driver added running lights, at least until LED's finally showed up.
 
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