Aux Switch, 12V DC2DC and 110V Inverter Install

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haleme

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I finally got around to finishing up the Aux Switch install on my 2500 this week.

My plan for the Aux switches was to use #1 and #2 to switch on power for a DC2DC charger on my travel trailer and an inverter to run a 110V outlet in the bed. Switches #3 and #4 are for rear spot and rear fog lights respectively.
Ram 2500 Wiring.jpeg

I custom built a wiring harness to send the power to the rear.
Invert is 500 watts (41 amps max) and used 6 AWG wiring. It is wild that the inverter came with 10 AWG direct to battery cables.
DC 2 DC charger is 20 amps and uses 8 AWG wiring.
2 runs of 14 AWG for the rear lights.

I have two big 120 amp relays for the two power points. These relays are controlled by the aux switch relays in the black box to the right.
IMG_20230419_110513027_HDR.jpg


Everything goes through a 70 AMP fuse mounted on the existing fuse box.
IMG_20230419_110517965_HDR.jpg

And the wiring from the rear to the front
Started with a harness I made to take power from the relays in the engine compartment to the rear of the truck.
IMG_20230413_154357250_HDR CLEAN.jpg
The TRAC connector for the DC2DC charger mounted in the rear bumper.
IMG_20230413_154353341 CLEAN.jpg
The wiring harness followed the factory wiring along the frame to the engine bay.
IMG_20230415_145835820_HDR.jpg
IMG_20230415_145842550_HDR.jpg
Used an existing hole in the internal bed frame to ground everything out.
IMG_20230415_145846384.jpg
I stubbed out the 12V positive for the inverted I will install in a future post.
IMG_20230415_145839462.jpg

Finally the rear spot and fog lights are incorporated into an OPT7 60" tailgate light bar. Attached with Neodymium Bar Magnets.
IMG_20230419_191438010_HDR CLEAN.jpg
IMG_20230419_191504643 CLEAN.jpg

It felt like a lot of work for very little to show, but I know it will be worth the time come our next camping trip.
 
OP
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haleme

haleme

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Got to complete and test the DC2DC charger this evening. Long story short, it works perfectly!

Need to wrap the cables, but that is a tomorrow job
IMG_20230517_231444855_HDR.jpg

The DC2DC charger is the blue black box on the bottom right. The box on the back wall with all the wiring has a remote switch I can use to turn the charger on and off from the cab. Going to get this remote synced up to the Home Link button.
IMG_20230517_231459432_HDR.jpg

And the success, 20 amps from the charger and 5ish amps from the 7 pin connector.
IMG_20230517_231510768.jpg
 
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haleme

haleme

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Finally got around to install the inverter in the bed of the truck this week. I'm using a Cobra 500 watt unit inside a sealed box mounted behind the left tire.
IMG_20230921_144255621_HDR.jpg
From the bottom.
IMG_20230921_144230342.jpg
And the control unit and 110V outlet in the bed.
IMG_20230921_144141722_HDR.jpg
It works!
IMG_20230921_144201478_HDR.jpg
 

tnctx02

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Awesome write up! Lots of good information and really nice job!
I plan some of these myself and I will use your post as a guide!
Thanks for taking the time to do this!
 

Wild one

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Awesome write up! Lots of good information and really nice job!
I plan some of these myself and I will use your post as a guide!
Thanks for taking the time to do this!
Garden Hose makes a great hose covering,a little better then the convulated covering the OP used.A long piece of wire makes a great fish tape to pull your wiring through the garden hose.
 
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