Rewiring battery bank to charger/inverter, couple of ?'s

Hi,

I used a 2 lug connector, and bolted this to my frame, then ran the 000 wire to this connector, then to the battery, so have the best of both worlds. When my motorhome engine is running, I can get about 100 amps from the alternator, and it will have a return path on the chassis frame, while not running the engine, the wire will go directly to the battery via low loss copper wire.

In your case, I would run the controller to your charger location, then #4 wire to the battery, there is no need for both the solar controller and charger to have separate wires to the battery. My guess is the charger is located near the fuse panel? You would also want #4 from the fuse panel to the charger/inverter, for the least amount of voltage drop, unless the fuse panel is already wired close to the battery via it's own large wire. Many times the factory wiring is pretty small.

If you will be installing 200+ watts of solar panels, then upgrading the truck to tow vehicle wiring is probably not needed. however if you really want to be able to recharge the trailer battery from the truck, then changing to #8 wire (or larger) with a isolator relay and quick connect 'anderson connector' would really make a big difference in the ability of the truck to recharge that large battery bank.

My solar system is 400 watts, and my RV uses about 35 AH daily to run just the refrigerator, CO and propane detectors. That is about what one 120 watt solar panel can produce in 1 day. Figure the amp rating on the panel times 5 hours, and you will get about the average solar production for one sunny day.

By the way, those batteries are about 75 pounds each, so you will be adding over 300 pounds to the hitch weight.

Fred.

HiTech wrote:
It is slightly better to run a dedicated ground than a well done frame ground.

This is pure subjective opinion. The frame will have considerably more cross section than 4AWG wire, and therefore offer less resistance.

One must assume that connections are "well done" in either case.

renoman69 wrote:
Run the wire every time. Frame grounds are way too unreliable.

Since when? Every automobile on the road has multiple circuits wired this way.

Does your starter have a ground cable all the way back to the battery?

Run the wire every time. Frame grounds are way too unreliable.

It is slightly better to run a dedicated ground than a well done frame ground. If they salt the roads there, a ground to frame may corrode more easily over time.

Jim

This is my battery bank setup using frame grounds at the battery bank. My converter/charger negative battery cable also is grounded to the trailer frame. I too am using 4AWG good quality marine grade battery cable.

When my converter/charger is operating I see a good 52-54AMPS DC Current being put back into the battery bank which tells me the frame ground connections are good.



My PD9260C is only about 5-feet away from the battery bank main switch but the 4AWG cable run to the DC Power Distribution Panel is around 12-feet away which also has the negative ground battery cable connection going to the trailer frame ground.

I did use the automotive method of tapping a hole into the trailer frame and uses a 5/16-inch thread tap. Then the Battery cable has the proper ring terminal with a STAR WASHER between the ring terminal and the frame ground to bite into the metal when tightned down. I always only use ONE BATTERY CABLE per frame ground connection.

The TAP BIT and Automotive Bolt and STAR washer is from PEPBOYS...


I might add that my install using this method since 2009 shows no signs of corrosion at the connection points.

Roy Ken