DC to DC charger wiring

[Schuess]

I am installing a Renogy 40amp DC to DC charger on my Reflection and F-250 using 4ga wire.
My question is there a reason why I need to run a black (ground) wire along with the red (power) wire the length of my truck up to my truck battery? Why can I not run the black wire to the chassis in the rear to save weight. I’d say money but I already bought the damn wire. The combined weight of both the wires is 10 lbs.

[traveldawg]

I ran both a dedicated positive and negative wire. I am pretty sure you can just use the frame - BUT..... not the chassis... Since Ford is now using aluminum panels grounding (and isolation / galvanic corrosion has become "a thing".

So be sure you use a good ground on the frame at the rear. Then take some voltage measurements when done to make sure the loss isn't too much. With my dedicate wires I think I still have maybe .01 or .02 volt loss.

Here is where I put my Anderson connector....

[Schuess]

Yeah, I didn’t mean chassis but frame. I was in the middle of the installation so I decided to play it safe and run a dedicated line. My setup looks similar but I bought the wrong plugs for the bed. I went with the 50amp plugs but the fittings were for 6 or more, not 4. Waiting now on the 125amp plugs which will take the 4 ga wire. Also, still waiting on the Renogy to do the trailer side. Work in progress…

[Butcher]

Too late, but I would have used the frame. Done right, the resistance has got to be lower and that is always a good thing. Saving money would not be a bad thing either.

[Soundsailor]

Too late, but I would have used the frame. Done right, the resistance has got to be lower and that is always a good thing. Saving money would not be a bad thing either.

OK, I'll bite. What would be the right way to install the wiring using the frame? I'm getting ready to install the wiring and would appreciate any help I can get. I don't have much experience with truck wiring, so please be specific. Pictures really help.

[Butcher]

Just a bit of common sense. Clean the surface of the frame, no paint or corrosion. Use a fastener that is large enough with the right torque. Nothing special, just common sense. Would not hurt to weather proof the area too. Find a space that is as much out of the elements as possible.

I certainly would not just slap a cable on a frame and call it good enough.

I just spent a bunch of time and money on LifePo4 batteries and will work on the solar next year. That will include the DC/DC converter. Sorry, no pictures this year.

[MoonShadow_1911]

OK, I'll bite. What would be the right way to install the wiring using the frame? I'm getting ready to install the wiring and would appreciate any help I can get. I don't have much experience with truck wiring, so please be specific. Pictures really help.

I would go with the following:

1. Wire brush head on my drill to remove the paint and stuff from the box frame, near the back of the truck.
2. #14 x 1" (1/4" to 3" Available) Hex Washer Head Self Drilling Screws, Self Tapping Sheet Metal Tek Screws, 410 Stainless Steel, 50 PCS https://a.co/d/7idAWVj
3. 1/4" Stainless Steel External Tooth Star Lock Washers (Pack of 100pcs) Marine Bolt Supply https://a.co/d/8z7IcmD
4. 10PCS Battery Cable Ends, 4 Gauge Wire Connectors 1/4 Copper Wire Lugs, Bare Copper Eyelets with Heat Shrink Tubing by HOUSUN https://a.co/d/5JhGiqe

This is for 4 GA fine stranded copper wire. You'll need a crimp tool for the lugs.

I highly recommend going with an "outside" or "heavy duty" sheath on the cable. It's just a thicker insulator jacket. It's more expensive, but when exposed to the elements they usually hold up longer.

If you can get to both sides of the wall of the box frame, then bolting the ground is preferable to using a self-tapping hex screw.

Also, if the cable is going to be run around a "sharp" edge, see if you can put a grommet there, or at least cut a small length of rubber hose, split it in half and screw it down to the metal edge.

[traveldawg]

I am installing a Renogy 40amp DC to DC charger on my Reflection and F-250 using 4ga wire.
My question is there a reason why I need to run a black (ground) wire along with the red (power) wire the length of my truck up to my truck battery? Why can I not run the black wire to the chassis in the rear to save weight. I’d say money but I already bought the damn wire. The combined weight of both the wires is 10 lbs.

Figured I toss in a photo of the charger too. Should have done this to begin with.....

And one more note, I wired from the battery (had to creat my own terminal), to a circuit breaker, to a solenoid controlled by an up fitter switch and then to the back of the truck.

[Schuess]

How did you wire your DC+ wire? I tried to wire mine to the running lights but it didn’t work. My running lights don’t seem to be getting 12 volts and I believe the DC+ requires a full 12.

[SolarPoweredRV]

How did you wire your DC+ wire? I tried to wire mine to the running lights but it didn’t work. My running lights don’t seem to be getting 12 volts and I believe the DC+ requires a full 12.

Exactly which DC+ wire are you referring too?

I don't understand your question?