2 12v batteries---Mallard TT help

RustyMacIntosh wrote:
1) Getting a charge to the house battery from the tow vehicle while traveling. I use a 99 Suburban. ... Or hardwire it from the pigtail connection at the trailer and Suburban.

opnspaces wrote:
I have run a charge wire from the front of my 1996 Suburban to the rear. The wire was already there from the factory, I just had to hook it up. And I have checked many times and it does recharge the batteries from 50% charge to full in the two hours it takes me to drive home from the desert.

OpenSpaces write up is pretty good regarding charging from a 12V power on a 7 pin connector, but you may or may not run into a problem.

Some time around 2000-2005 ALL cras and light trucks start using "smart charging systems". Various manufacturers do it differently and even the same manufacturer have made changes since they first started. These smart charging system put out the MINIMUM voltage to keep the starting battery charged, typically between 13.2V and 13.8V (about 2-5 minutes after the engine has started). This is NOT ENOUGH VOLTAGE TO CHARGE A HOUSE LEAD ACID BATTERY BANK ! Installing heavier wire will NOT improve this !!

What you need is a DC-DC battery charger. Renogy, Redarc and Ctek all make them. They actually boost the available voltage on 12V power pin in order to properly charge the house batteries.

RustyMacIntosh wrote:
2) Issue two that I need to solve is installing two 12v batteries rather than one at the outside front of the Mallard. I am thinking, if I got this right, that I can put two 12v batteries behind the propane tanks.

You would be much better off with TWO 6V golf cart batteries. They will give you more power, last longer and probably cost less.

NOCO does make a plastic battery box that will hold two 6V golf cart batteries, but it needs support rail underneath where it is mounted.