Grounding question on a new project..

[smlobx]

Hi everyone. I’m starting a new project build with my new Jeep Gladiator. I will be turning it into a more off-road long distance overlanding vehicle. I will be installing a second battery (BattleBorn) under the canopy in the bed that will be controlled by a Redarc BCDC 1240 (https://redarcelectronics.com/products/dual-input-40a-in-vehicle-dc-battery-charger ) which is solar capable in addition to getting a charge from the vehicle.
My basic question (please don’t laugh too loudly) is about grounding...

As you can imagine (or you can see in the instruction manual in the link above) there are several points that need to be grounded. I have found a great place to run the ground to on the frame under the bed of the gladiator that has a nut welded into it from the factory.

My questions what is the best way to run the grounds? Here are some possible options and I would like those of you with more knowledge on this to please chime in..

OPTION 1
Run a single large ground from the aux battery to the chassis ground and run all the other grounds to the battery’s negative terminal.

OPTION 2
Run a single wire from the chassis ground to a bus bar and connect all the grounds to that including the aux battery.

OPTION 3
Run all the ground wires to the chassis ground separately. This is probably my least favorite option.

OPTION 4
???

Thanks. I want to learn as I do this so I can fix things down the road if/when that happens.

 

[Wandering Sagebrush]

I’m voting for option 2.

 

[Vic Harder]

Likewise, option 2

 

[Kolockum]

First of all good question. Most people spend a lot of effort on getting power to something only to hook up a crappy ground and then wonder why it doesn't work quite right.

I would do option 2. It will look cleaner, be easier to make and check connections. I would recommend using a buss bar with screws and use ring connecters preferably soldered onto the wires. (A lot of electrical issues I have have seen had something to do with a bad ground). Just make sure it is well grounded and/or the cable to the battery is sufficiently sized.

 

[smlobx]

Thanks for your input guys. Fortunately I don’t have a problem asking for help when I’m out of my comfort zone (unless we’re talking about asking for directions!).

Kolockum I am thinking of a bus bar like this..

https://www.amazon.com/Blue-Sea-Systems-Common-10-Gang/dp/B0091VHLW4/ref=pd_bxgy_2/138-3357101-7785251?_encoding=UTF8&pd_rd_i=B0091VHLW4&pd_rd_r=d1ef4226-a352-4800-b7db-e16081ef1195&pd_rd_w=2Zciu&pd_rd_wg=4s3B6&pf_rd_p=f325d01c-4658-4593-be83-3e12ca663f0e&pf_rd_r=3JCGH54K0P26ANPG8TKN&psc=1&refRID=3JCGH54K0P26ANPG8TKN

I have been reading a lot about the proper way to make good solid connections and crimping, soldering and heat shrinking are all going to be part of the process.

 

[Vic Harder]

Use some of this stuff too if corrosion is a concern.
Amazon.com: Dielectric Grease/Silicone Paste/Waterproof Marine Grease (8 Oz.) Made in USA- Excellent Silicone Grease: Automotive

 

[Wandering Sagebrush]

That bus bar is fine. FWIW, I’m not a fan of soldered connectors. I’ve had them break in areas that received a lot of vibration. I much prefer a good quality crimp-on that is crimped properly.

 

[Kolockum]

Thanks for your input guys. Fortunately I don’t have a problem asking for help when I’m out of my comfort zone (unless we’re talking about asking for directions!).

Kolockum I am thinking of a bus bar like this..

https://www.amazon.com/Blue-Sea-Systems-Common-10-Gang/dp/B0091VHLW4/ref=pd_bxgy_2/138-3357101-7785251?_encoding=UTF8&pd_rd_i=B0091VHLW4&pd_rd_r=d1ef4226-a352-4800-b7db-e16081ef1195&pd_rd_w=2Zciu&pd_rd_wg=4s3B6&pf_rd_p=f325d01c-4658-4593-be83-3e12ca663f0e&pf_rd_r=3JCGH54K0P26ANPG8TKN&psc=1&refRID=3JCGH54K0P26ANPG8TKN

I have been reading a lot about the proper way to make good solid connections and crimping, soldering and heat shrinking are all going to be part of the process.

That is the exact type that I was talking about. And Vic is dead on with the dielectric grease.

Use flux as it will make soldering easier (helps distribute the solder). I use marine heat shrink due to the additional coating on the inside that melts and helps provide a waterproof coat.

Here is the gentleman (Jeep Hammer) that I learned most of my electrical stuff from over on Jeep Forum. His posts start at #3. He is a legend over on Jeep Forum.
https://www.jeepforum.com/forum/f8/been-reading-good-book-jeephammer-833631/

 

[pvstoy]

Due care soldering small wires. You just want it at the connector not allowing the solder to wick up the wire. If it does then run the risk with vibration the soldered wire will crack. Well crimped and good coverage with heat shrink will last you. Cover the heat shrink up to the ring terminal not allowing moisture to get to the crimp.

 

[ntsqd]

That bus bar is fine. FWIW, I’m not a fan of soldered connectors. I’ve had them break in areas that received a lot of vibration. I much prefer a good quality crimp-on that is crimped properly.

Me too. I used to solder all of my terminals and was very careful to not let the solder wick out of the terminal's barrel. One fatigue failed anyway and left me in the dark in the middle of CA's El Paso Mtns. with no power at all. At least I knew which wire it was!

Buy a good crimper and learn how to use it. I consider one like this to be the bare beginnings of a decent crimper: https://www.amazon.com/gp/product/B00776SJJO
Buy a good striper and learn how to use it, too. I carry one of these for field use: https://www.amazon.com/gp/product/B008PVUGUU
The thing that needs to be understood, and rarely is, is that poor striping tools & techniques can be at fault almost as often as a poor crimp. In aircraft or military wiring looms a nicked strand is cause for the whole wire to be replaced. Good striping tools don't nick the strands, bad ones or poor techniques do.

I recently had the job of fixing one of those butt-splices that you supposedly can just heat up and it solders the connection and shrinks the adhesive lined heat-shrink all at the same time.We had just finished pulling the grade on Nadeau Rd. out of Searles Valley and were just past the pavement crossing when the owner of the truck reported that his truck was boiling over. Turned out that was because one of those connectors had gotten hot enough under the hood to let go of one of the wires and now the electric radiator fans didn't work.

As to the original question, I'm a fan of the fewest connections that can be made in a circuit. That isn't to say that they should all be piled up under the clamp nut of the battery terminal. I've taken to using the so-called "military battery terminals" because they allow me to make many such connections at the battery without it being a jumbled mess.