One Aftermarket Electrical Harness to Rule Them All (1 Viewer)

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Joined
Mar 4, 2017
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San Francisco, CA
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Hi everyone -

As I've spent most of February plotting electrical upgrades to get my rig ready for camping with the kids for a few days at a time (up to a week) this summer and beyond. As part of the planning, I've been reading around on here all of different electrical aftermarket upgrades folks have made on their rigs ... and about some of the nightmares associated with, shall we call it, organic?, wiring decisions made as part of the process.

As a recovering electrical systems engineer, I wanted to step back and actually plan out, and post for everyone, what I would consider a "proper" approach to build a power distribution system across a rig to handle the majority of necesary loads that could be thrown at it, as well as some considerations for safety and failure points, smart wiring, etc. This is different than what @NLXTACY did for the "how to" ... that is also important, but I wanted to take one step even further back and look at ALL the loads to be considered across the vehicle first.

HUGE thanks already to everyone here whose posts I've been snooping on and taking notes. There are far too many individuals to thank off the bat, but if you've contributed to electrical "How-to" here in the 80s-tech forum over the last decade, there's a good chance I've read through your posts in-depth to start planning this out.

So ... based on the initial requirements I laid out above (safely camp for up to a week off-road with a couple of kids, me, maybe the wife and dog in a relative comfort),and all your feedback below, I've come up with the following aftermarket loads that should be planned for:
  • 2m Radio
  • CB radio (easily removable / swappable)
  • Fridge
  • 1500W peak Inverter
  • Camp Lights
  • Front light bar
  • Driving Lights
  • Interior LED upgrades
  • Rear Hatch Lights (inward / down)
  • Air compressor (York OBA or portable)
  • 10 x 10W USB outlets - 6 x front, 2 x middle, 2 xrear
  • 12V power outlets - 1 x front / 2 x rear
  • Winch
  • 1 x battery tool charging port outlet or similar
  • Nav / head unit
  • Backup cam
  • relevant charging for phone / tablet for OBD BLE
  • Upgraded horn
I have already installed a dual battery system (IBS with Relay Boost) and will likely add ~200-300W of solar to charge batteries if I get in a tight spot.

All-in, I'm estimating ~ +1500W peak load (excluding solar source) plus the winch ... not that it would all run at once, but those are the incremental accessories to plan across a rig.

Is there anything else I'm missing?
 
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Hmm. I haven’t added my system up for peak amps since I know I will never run everything all at once.

Here’s what I have added:

  • Blue Sea Systems ML-ACR 7622 12V DC 500A Automatic Charging Relay with Manual Control (dual battery control) with 2/0awg welding cables
  • Photoman bracket w/ 150AMP alternator, 200amp ANL inline fuse
  • Military battery terminals
  • (2) Blue Sea 12-circuit fuse blocks (one in engine bay and the other in passenger rear quarter panel)
  • (2) 27F batteries
  • 1500w inverter
  • Puma 12v compressor
  • Warn winch
  • Prewired for frig
  • Garmin navigation with bluetooth backup camera
  • Falcon Zero dashcam
  • Kenwood TM-V71A dual band ham radio
  • Uniden 520XL CB radio
  • Front 20" bumper LED light bar
  • Dual 4" LED light pods on rear bumper
  • (4) 12v AUX sockets
  • (2) 2-port USB sockets
  • Upgraded PIAA horn with 10awg wiring
  • LED interior lighting
I’m sure I’m forgetting something. Check out my build thread for pictures.
 
@ChaseTruck i am an idiot and forgot that I have a winch installed already.

Re: Ham radio ... I was considering and frankly haven’t seen a lot of debate in here on the value so jury is out ... but a worthwhile load to design in the first time around. Consider it added to the list - thanks for calling out!
 
@chap79 thank you as well for input ... much appreciated. I’ll finish speccing our list and re-post here in next day or two based on all involved. I have already installed dual battery and IBS as well ... dual battery for this type of set-up is a given. Again, thanks for the feedback!
 
@ChaseTruck i am an idiot and forgot that I have a winch installed already.

Re: Ham radio ... I was considering and frankly haven’t seen a lot of debate in here on the value so jury is out ... but a worthwhile load to design in the first time around. Consider it added to the list - thanks for calling out!
You're in the 80s tech section, but there's a separate forum for communication and navigation.

CB radio is like Dixie cups and string compared to the least expensive ham radio.
It is dead technology that hasn't changed or seen any development since the late 1970s.
It is kept alive by those who simply don't know better.
 
You're in the 80s tech section, but there's a separate forum for communication and navigation.

CB radio is like Dixie cups and string compared to the least expensive ham radio.
It is dead technology that hasn't changed or seen any development since the late 1970s.
It is kept alive by those who simply don't know better.
The only reason I installed a CB is because TLCA still requires it at some events :meh: But a cheap handheld can be used if one doesn’t want to mount a unit in the cab for using once a year.
 
The only reason I installed a CB is because TLCA still requires it at some events :meh: But a cheap handheld can be used if one doesn’t want to mount a unit in the cab for using once a year.
LOL. That's exactly why I bought a Midland CB. The first and last time I used it was at Cruise Moab inspection. For the entire event I was on 2M.
 
A typical 50w 2m/70cm uses 11-12amps on transmit. Use min 12ga wire for the CB run so it can be upgraded to ham in the future if desired.
 
Re: Ham radio ... I was considering and frankly haven’t seen a lot of debate in here on the value so jury is out ... but a worthwhile load to design in the first time around. Consider it added to the list - thanks for calling out!
I didn't mean to break the HAM vs. CB stuff loose yet again.
I mentioned it because wiring a HAM radio takes a bit of effort & planning. For a CB, you can pull power from pretty much anywhere on the truck and it'll somehow work.
 
Very interested to see this pan out. I'd like to build a harness out eventually for all the components so that as i add them on i can just plug in and go versus ripping into wiring every time. I've done that before and it always ends up a rat's nest or you end up redoing it every time. Planning for each component and understanding what is needed would be awesome information to have.
 
Very interested to see this pan out. I'd like to build a harness out eventually for all the components so that as i add them on i can just plug in and go versus ripping into wiring every time. I've done that before and it always ends up a rat's nest or you end up redoing it every time. Planning for each component and understanding what is needed would be awesome information to have.

That is EXACTLY why I'm doing this ... way better than rats nest :) I've been holding off on all major electrical work for this exact reason
 
When I designed my system I wanted an additional fuse block in the front and rear of the truck. I used two 100amp fuse blocks. Based on the distance from the battery I used 4awg welding wire to the fuse blocks going through a 100amp breaker for each circuit. All gauge of wiring I used was dependent on the amps being used and the distance of the run.

The front fuse block is a 50/50 split of hot power and switched power. The rear block is hot all the time. Also tied into the rear fuse block and tee’d off is the puma compressor, going through another 70amp breaker.

There’s a lot of ways to to do power distribution, just make sure you are doing it safe.
 
Thanks everyone for your feedback on requirements. I’ve updated the initial post with list of content. Keep it coming!

Addressing the comments of a few folks, upgrades like a bigger alternator, fuse panels, relays, second battery, associated controller etc will be “designed in” as part of the process as this goes along. I’ll also do my best to post one lines and schematics (all by hand) as I go
 
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I’ve got a dual battery power platform setup in my truck. I’ve got a good amount of auxiliary circuits run also. Calculating wattage needs and use, I measured that I can use up to maybe 1000 amps MAX while driving, in addition to the regular engine and driving power needs. Parked I use maybe 300 watts MAX but that would be very unlikely. Usually it’s under 100 watts.
 
Ok ... thanks a ton for everyone who gave feedback or input, in particular @Shoredreamer for the idea of how to delineate loads ... I took it a step further with having engine on / both / engine off requirements.

Consider the below as a block diagram / high-level schematic that roughly aligns front > rear of our rigs. Nothing is connected yet, and very few unpowered components are listed - this is my first build from memory of my rig plus reading through dozens of others here.

Don't assume that you need to have all of the elements listed (e.g. rock lights ... definitely a "nice to have" not a must have") ... think of it more as a pick-list so that as this comes together, it is a high level view of what you may want to have at a given physical location (approximately) in your vehicle.

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Next up - I'll be looking through and doing 1-line schematics and starting to lay out switches / breakers.

Based on what you see - what are your thoughts? Is there anything significant I'm missing?
 
Next update ... here's the first pasas at a functional one-line diagram - basically, breaking those blocks up and starting to tie them together. From a layout strategy, I landed on three busses / aux fuse panels. One under the hood just for lights, one somewhere either under hood or under front seat for interior components, and one in the rear for all the rear lights. I also moved a few items around from the initial layout, as I wanted to minimize my front-to-rear cable runs - heavy, thick, and just another failure point. By adding a distribution point in the rear cargo area, I'll be able to tie in a solar voltage regulator and dump up to 25-30A into the rear cargo panel as well at any point, which minimizes current draw from the battery at the front; i can also de-link batteries at IBS and operate majority of system on closed loop of aux battery, solar panels, and associated loads.

I also believe a NC automatic relay tied to ignition system can enforce "engine on only" requirement. It requires an additional 2-3 wires to be run, but they're much smaller - 20 ga or smaller - just to control relay. Has anyone done this type of setup before?

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Very nice layout. Thanks for posting as it gives a nice visual to mentally layout a wiring plan.

The only comment I would make is to add an emergency disconnect (visibly labeled switch or CB) at each power source. In a short circuit/electrical fire situation seconds count and being able to cut off ALL sources of power to the truck quickly can make the difference between melted wire or a melted truck.

With only the stock battery, it is easy enough to cut the negative and isolate it from the truck. As we add multiple batteries and solar however, sometimes with hidden interconnection points, it becomes more of a time intensive process to quickly remove power sources from the truck.

Solar is live ALL the time light is hitting the panels and it is important to have an easily accessible solar disconnect as well. I work in solar for a living and there is a reason electric codes have been modified to require emergency disconnects before a solar array feeds a building. Our rigs are much smaller systems, but the 50-200 Watts of solar we put on the roof is just as capable of starting a fire as the larger building mounted arrays.
 
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