DC to DC Charger wiring on new TV

[69SoulShine]

I picked up my New F-350 King Ranch yesterday. Woo hoo! Now I have to wire it for my Victron 30 amp DC to DC charger. It was previously wired by others with a 1/0 positive cable from battery to a Anderson plug at bumper. And grounded to the frame near the bumper from The Anderson plug.
My question is should I go back with the ground running through the frame or would it be better to run a negative wire back to the battery? I’m also considering downsizing the wire to #2. from what I understand that should be sufficient for the 30 amp charger?
Thanks.

[TitusNW]

I have a Renogy 40A DC-DC and used 4ga cable off the positive of the truck battery to an Anderson connector at the tailgate. Used the truck frame for the ground connection to the Anderson connector.


I'm happy with the performance.


Steve

[uncle_bob]

Hi

Grounding only to the frame is not a great idea for something like this. It might work well sometimes and not so well other times. Best to run the ground wire. Best solution is to do both ....(run the ground wire and hook to the frame).

Bob

[richard5933]

I agree that it's best to run a dedicated line for both the positive and negative.

By using the frame as the ground you're putting more load on the existing ground strap/cable serving the tow vehicle, and they are prone to corrosion and degradation over time. Problems with poor grounding is a common problem when a vehicle is having charging issues - might not be a big deal on a new truck but it can creep up on you faster than imagined, especially if you live somewhere with winter or salt spray from the coast.

[jeffmc306]

69SoulShine, congratulations on your new F350!

I’m with Uncle Bob and Richard on this. I pulled 4 AWG TEMCo wire from the battery to the bumper for our 40A Renogy. I used a high temp sleeve for the front section (belt and suspenders) then corrugated plastic to the bumper.

I used a 60A MRBF fuse mounted to the battery busbar, part of the outfitter’s option. This makes for a very compact installation. Also, I pulled a single 12 ga. wire for the Renogy’s ignition signal and wired it to an Aux switch programmed to turn off when the ignition is off. This way I can chose to turn the DC-DC charger off if I ever need to.

At the bumper, I used a Trailer Vision holder for the Anderson plug with a cover. Keeps everything nice and clean.

I have read that you can experience voltage drop when using the frame as a ground, likely to Richard’s point about overloading the existing grounds. YMMV!

Good luck and enjoy your new rig!

[dsatwork]

I also agree with running the ground to the battery but, the math was simple for the distance and 30amp, I used 6 gauge wire and was able to route it away from anything hot on my 2018 Ram 6.7.

[markuscis]

Originally Posted by jeffmc306

69SoulShine, congratulations on your new F350!

I’m with Uncle Bob and Richard on this. I pulled 4 AWG TEMCo wire from the battery to the bumper for our 40A Renogy. I used a high temp sleeve for the front section (belt and suspenders) then corrugated plastic to the bumper.

I used a 60A MRBF fuse mounted to the battery busbar, part of the outfitter’s option. This makes for a very compact installation. Also, I pulled a single 12 ga. wire for the Renogy’s ignition signal and wired it to an Aux switch programmed to turn off when the ignition is off. This way I can chose to turn the DC-DC charger off if I ever need to.

At the bumper, I used a Trailer Vision holder for the Anderson plug with a cover. Keeps everything nice and clean.

I have read that you can experience voltage drop when using the frame as a ground, likely to Richard’s point about overloading the existing grounds. YMMV!

Good luck and enjoy your new rig!

Jeff, Where did you get that frame mounted anderson mount? BTW I'm running both ground and positive 4 gauge.

Never mind, found it on Amazon, Thank You for the inspiration!

[richard5933]

Originally Posted by markuscis

Jeff, Where did you get that frame mounted anderson mount? BTW I'm running both ground and positive 4 gauge.

Never mind, found it on Amazon, Thank You for the inspiration!

I got mine from Amazon

https://www.amazon.com/stores/page/6...o&ref_=ast_bln

[Life is a Highway]

I have your vehicle only a F-250. The rear ground short frame wire is fine as long as it is with proper size cable and a clean ground with a bolt connecting it. I verified that with voltage drop when the system was under load.

In addition I used a fused battery cable from the alternator positive post to a Blue Sea Solenoid. The other side carries the current back to the Anderson connector. I used the Ford up fitter switch #2 to control the Blue sea solenoid current back to the Anderson connector. I like to be in control of that circuit either on or off! I do not like it wired hot all the time.


The Anderson connector is mounted in a composite holder like Jeff's

[69SoulShine]

Thanks everyone for the helpful info and advice. This community is great.!

[69SoulShine]

So while in the process of installing my dc to dc charger (truck side) I came across this warning in the owners manual. My question is has anyone had a discussion about this with someone from Ford? And what are your thoughts on this?

[jeffmc306]

Originally Posted by 69SoulShine

So while in the process of installing my dc to dc charger (truck side) I came across this warning in the owners manual. My question is has anyone had a discussion about this with someone from Ford? And what are your thoughts on this?

While not a Ford, our RAM also has a BMS sensor connected between the battery and the truck’s ground cable. I connected my Renogy’s DC-DC charger’s negative cable to the stud on the BMS, not the battery. See the photo attached.

This way all the current is measured by the BMS (similar to a Victron BVM’s shunt). I think if you do the same you’ll be in line with Ford’s recommendation.

[TitusNW]

Attached is the setup of a 2021 F-150. When I was thinking of the path of electrons to keep the Ford BMS in the loop I considered the ground strap (with the white tag) but didn't know if the BMS would be in the loop. I opted to ground my Anderson connector to the frame and let the electrons find their own way to the battery.

Steve

[69SoulShine]

This looks like it would send it through the BMS.

[69SoulShine]

One more concern that I see in the owners manual mentions if the BMS sees excessive current drain it will start shutting down systems. Here's a photo of that screen.

[TitusNW]

I read those same notes before I installed my charger. You can also read the Ford forums for posts relating to "System off to save battery" and/or "low battery". It seems that many owners have issues with the OEM battery and short commutes. More unbelievable to me, it seems many put their trucks on battery maintainers overnight!

I installed my DC-DC charger Aug 2023 and have no troubles over the last 20K miles. Regarding the Ford warnings, I use the 7-pin charge line to power a wireless switch in the trailer so I can turn the charger ON of OFF from the truck. I don't have it on unless I'm rolling down the road for good alternator cooling. If the batteries are not topped off, I turn OFF the charger for road blocks or traffic jams.

Before my recent trip to Alaska I chose to replace the OEM battery with a new Interstate H7 battery. I figured why risk a big trip with a 36 month old battery. They don't build them like they used to...

It all works for me but I do try and be gentle on the alternator.

Steve

[jeffmc306]

Originally Posted by 69SoulShine

This looks like it would send it through the BMS.

Yes, that would be the same as what I did. The BMS sits between the ground wire and the battery from what I can see from TitusNW’s photo of his.

If you connect it to the stud on the top, it meets the Ford recommendation.

[nvestysly]

I agree with others who've indicated to run both + and - in close proximity to the battery. While I am no expert, I've heard of too many problems with "ground loops" (attaching ground to a point that is remote from the positive terminal). Based on the couple of pictures in earlier posts, I wouldn't hesitate to connect the ground at the vehicle chassis where the ground cable is attached from the battery. That's what I did on our GMC Sierra.

[TravelTales]

Originally Posted by 69SoulShine

Thanks everyone for the helpful info and advice. This community is great.!

Thanks all for the great dialog.
I’m looking at dc to dc charging to address the problem of having to keep propane on if I want the fridge to stay cool.

We have a two way - runs on shore power or propane.
should I
A. Replace the propane fridge with a new 12v
B. Install dc to dc charging - if so can a 50amp dc to dc put enough energy into system to run 120v fridge.

Where do I connect the power coming out of the dc to sc charger ?

Thanks
Michael

[richard5933]

Originally Posted by TravelTales

Thanks all for the great dialog.
I’m looking at dc to dc charging to address the problem of having to keep propane on if I want the fridge to stay cool.

We have a two way - runs on shore power or propane.
should I
A. Replace the propane fridge with a new 12v
B. Install dc to dc charging - if so can a 50amp dc to dc put enough energy into system to run 120v fridge.

Where do I connect the power coming out of the dc to sc charger ?

Thanks
Michael

The power output from your DC-to-DC charger goes to the same place your converter goes. It would also be the same place your solar charge controller goes if you have solar. That place is the bus bars for the positive and negative, if you have bus bars. If not, then where ever all your connections to your battery bank are.