Dual Battery setup with Blue Sea Add A Battery Kit

[LC4LIFE]

I did not fuse them there is really no need. The ML-ACR connects and disconnects the two batteries. I used 2 gauge for the batteries, and stepping down to 4 for the power to the back.

At a minimum, I would fuse the one going from the starting battery to the ACR. I always fuse both though, with BlueSea MRBF. Just because the ACR disconnects the batteries it does not mean there is no voltage on the cables from each battery. The only argument I can agree with for not fusing is if the purpose of your ML-ACR is to combine batteries to winch. Winching could pull enough amps to pop fuses at the battery terminals. Beyond winching, I see no electrical demand that would warrant opting out of protecting the cabling and preventing a fire.

 

[rannon]

At a minimum, I would fuse the one going from the starting battery to the ACR. I always fuse both though, with BlueSea MRBF. Just because the ACR disconnects the batteries it does not mean there is no voltage on the cables from each battery. The only argument I can agree with for not fusing is if the purpose of your ML-ACR is to combine batteries to winch. Winching could pull enough amps to pop fuses at the battery terminals. Beyond winching, I see no electrical demand that would warrant opting out of protecting the cabling and preventing a fire.

Ok great, thanks for weighing in on that. And thank you for the link. Since I'm in the stage of just gathering parts I'll grab the MRBF. Cheers!

 

[rannon]

Ok great, thanks for weighing in on that. And thank you for the link. Since I'm in the stage of just gathering parts I'll grab the MRBF. Cheers!

In terms of installing that, would that go onto a battery post, and then the wire going to the ML starts from that block? Or would you put it mid-way down the wire to the ML?

 

[LC4LIFE]

In terms of installing that, would that go onto a battery post, and then the wire going to the ML starts from that block? Or would you put it mid-way down the wire to the ML?

correct, at the battery terminal.

 

[OffRoadScott]

At a minimum, I would fuse the one going from the starting battery to the ACR. I always fuse both though, with BlueSea MRBF. Just because the ACR disconnects the batteries it does not mean there is no voltage on the cables from each battery. The only argument I can agree with for not fusing is if the purpose of your ML-ACR is to combine batteries to winch. Winching could pull enough amps to pop fuses at the battery terminals. Beyond winching, I see no electrical demand that would warrant opting out of protecting the cabling and preventing a fire.

What size would you recommend for the MRBF?

 

[LC4LIFE]

What size would you recommend for the MRBF?

200amp for the ML-ACR. That’s good for that length and gauge of wire.

 

[BucketEighty]

I’m running a Blue Sea ML ACR and I had problems with the Auto function until I ran a big copper cable between the two ground terminals on the two batteries. Initially I had both batteries grounded to the vehicle body and both batteries grounded to the engine block but there was enough resistance in the ground path that the ACR would not always link the batteries when the engine was running to charge the second battery. It’s critical that you have near zero resistance between the two battery ground terminals for the ML ACR auto function to work right. Once I put a great big cable from ground to ground the ML ACR worked flawlessly. Also don’t over-torque the battery connection lugs on the ML ACR or you can break the plastic housing I broke one and Blue Sea replaced it under warranty.

 

[rannon]

correct, at the battery terminal.

Thanks! And I just saw the HuddExpo in your signature - will your skid plate be back in stock soon?

 

[rannon]

I’m running a Blue Sea ML ACR and I had problems with the Auto function until I ran a big copper cable between the two ground terminals on the two batteries. Initially I had both batteries grounded to the vehicle body and both batteries grounded to the engine block but there was enough resistance in the ground path that the ACR would not always link the batteries when the engine was running to charge the second battery. It’s critical that you have near zero resistance between the two battery ground terminals for the ML ACR auto function to work right. Once I put a great big cable from ground to ground the ML ACR worked flawlessly. Also don’t over-torque the battery connection lugs on the ML ACR or you can break the plastic housing I broke one and Blue Sea replaced it under warranty.

Interesting. Thanks for the recommendation. I'll consider that when mocking this up!

 

[BucketEighty]

I routed the cables (both positive and negative) under the upper radiator core support piece, where the headlight wiring loom is routed. It’s a few bolts to pull that radiator core support piece off and then easy and short cable routing between the two batteries.

 

[BucketEighty]

 

[RiverCityDave]

View attachment 3675144

I did the same. Super clean and avoids hassles.

 

[Fosters]

I situated my acr infront of my starter battery and then routed the other wire through the rad support as above…my main goal is to avoid wires and such on the air filter side for turbo install purposes and avoidance of heat induced damage

 

[Fosters]

Thanks to all who participated in this discussion…finally motivated my to actually wire the remote switch into the cab if my truck…thanks to @OffRoadScott for the witsend switch schematic

 

[OffRoadScott]

Thanks to all who participated in this discussion…finally motivated my to actually wire the remote switch into the cab if my truck…thanks to @OffRoadScott for the witsend switch schematic

You are welcome. Take your time and double, triple check your work prior to finally energizing the system.

 

[MANUCHAO]

any suggestions after having lived with this for a while?

I added a solar panel (185 W) to the pop-up. If i would do it again i would install batteries else where but the engine bay... heat and vibrations kills batteries.... looking at adding a lithium set up(3rd batt-stand alone) for the solar panel.... can't complaint... set up is been awesome..!!