Truck to trailer charging recommendations

[JCDriller]

I've building an expo trailer and it is equipped with 2 G31 odysseys, my tow vehicle is equipped with 2 G34 odysseys.

I currently have a solar charger installed along with a shore power battery charger, other than the small battery for the emergency breakaway that connects to the 7 pin I don't have any electrical hook up to my tow rig.

My initial plan was to run an ignition hot isolator (pac200) that also had a remote override switch through a 100a circuit breaker with 4 ga copper to the rear of the vehicle where it would end in an Anderson plug. On the trailer I can just have an Anderson plug with copper that runs back to a 100a circuit breaker then to the batteries.

Any reason not to charge the trailer in this manner? I don't plan on using my vehicle to maintain the batteries daily, for that I'll be relying on solar or shore, but when traveling I'd like to be able to top them off from the alternator. Plus I have solar on the roof rack of my 4R so I could keep the trailers fridge running if parked in a parking lot without pulling from the batteries.

I guess it comes down to B2B or direct wire. My thoughts are I'd like to get more amps in faster with direct wiring. Sound logical?

 

[mep1811]

I use Toad Charger .

http://www.lslproducts.net/ToadChargePage.html


Keeps Your Dinghy Vehicle
FULLY CHARGED...
No More Dead Batteries!

Automatically charges and maintains the battery in your dinghy vehicle (or "Toad") while you're towing it - Eliminates battery discharge problems due to leaving the ignition switch on, supplemental braking systems, etc.
The COMPLETE SOLUTION for dinghy vehicle battery charging!


TOAD-CHARGE™
Towed Vehicle Battery Charger/Maintainer Kit



Prevents Dinghy Battery Drain
when towing behind your motorhome.
Powerful 10 Amp Max. Output
Solves the toughest discharge problems - Automatically adjusts charging current to compensate for any drain on your dinghy battery.
Complete - Nothing Else To Buy
Includes your choice of 60' or 40' cut-to-length wire harness, Charge Regulator, Circuit Breaker, all mounting hardware & connectors, illustrated installation instructions.
Installs Permanently
No need to remove system when not towing your dinghy vehicle.
Unplugs When Not In Use
Center harness stows with your tow bar
Completely Automatic
No more pulling fuses and relays in your dinghy vehicle every time you tow it!
Fully Independent Connections
Provides its own power & ground connections to the dinghy battery - Completely unaffected by any existing wiring and connectors to dinghy vehicle.

Prolongs Dinghy Battery Life
Prevents destructive deep discharges - Pays for itself the first time you don't have to replace a ruined battery!

Designed With Safety In Mind
Fully protected against overloads & short circuits at both ends of the wire harness.

LED Status Indicators
on Charge Controller monitor all charging functions, warn against improper hook-up


Rugged, Reliable Components
Weatherproof, epoxy-encapsulated Charge Controller & Circuit Breaker - Extra-thick 12 gauge wire harness delivers maximum charging current - Vinyl-sleeved for weather and abrasision resistance.


Universal Fit
Fits all motorhomes, all dinghy vehicles.

 

[JCDriller]

I use Toad Charger .

http://www.lslproducts.net/ToadChargePage.html


Keeps Your Dinghy Vehicle
FULLY CHARGED...
No More Dead Batteries!

Automatically charges and maintains the battery in your dinghy vehicle (or "Toad") while you're towing it - Eliminates battery discharge problems due to leaving the ignition switch on, supplemental braking systems, etc.
The COMPLETE SOLUTION for dinghy vehicle battery charging!


TOAD-CHARGE™
Towed Vehicle Battery Charger/Maintainer Kit



Prevents Dinghy Battery Drain
when towing behind your motorhome.
Powerful 10 Amp Max. Output
Solves the toughest discharge problems - Automatically adjusts charging current to compensate for any drain on your dinghy battery.
Complete - Nothing Else To Buy
Includes your choice of 60' or 40' cut-to-length wire harness, Charge Regulator, Circuit Breaker, all mounting hardware & connectors, illustrated installation instructions.
Installs Permanently
No need to remove system when not towing your dinghy vehicle.
Unplugs When Not In Use
Center harness stows with your tow bar
Completely Automatic
No more pulling fuses and relays in your dinghy vehicle every time you tow it!
Fully Independent Connections
Provides its own power & ground connections to the dinghy battery - Completely unaffected by any existing wiring and connectors to dinghy vehicle.

Prolongs Dinghy Battery Life
Prevents destructive deep discharges - Pays for itself the first time you don't have to replace a ruined battery!

Designed With Safety In Mind
Fully protected against overloads & short circuits at both ends of the wire harness.

LED Status Indicators
on Charge Controller monitor all charging functions, warn against improper hook-up


Rugged, Reliable Components
Weatherproof, epoxy-encapsulated Charge Controller & Circuit Breaker - Extra-thick 12 gauge wire harness delivers maximum charging current - Vinyl-sleeved for weather and abrasision resistance.


Universal Fit
Fits all motorhomes, all dinghy vehicles.

This is a nice charger, I looked at it, but it has limited amps out like all B2B chargers. Unfortunately this one is only 10amps which isn't high enough.

Right now I'm running a standard alt., but hope to replace mine with a high output one soon. I want to maximize the amps that the trailer batteries can pull over my long AND short drives.

 

[C-Fish]

Our Turtleback receives enough of a charge from the standard 7 pin wiring during travel (alternator) and when coupled (solar from FJC) in camp...

Not sure why you need more amperage?

 

[DiploStrat]

Nothing Magic about a Trailer, other than ...

the need to disconnect and the fact that the batteries are further from the alternator.

So all of the maths are the same - figure the size of your battery bank, the charge rate needed, and compensate for the long wires.

All of these subjects have been beaten senseless in this forum, many times.

To your specific question of B2B vs. relay: The wire gauge will be the same, the only question is your vehicle's charging voltage. If it is high enough, go with a relay. If not, raise the vehicle voltage or use a B2B. If you use a B2B, put it in the trailer for maximum benefit. I like the REDARC units as they are ruggedized and don't need a fan.

 

[Bbasso]

Seems almost like you might not need to charge from vehicle to trailer...
What I mean is if you have done the math on the power consumption, the trailer's solar should be able to keep the battery bank full and healthy.
Unless I missed something...