Adding a 12V Outlet

ScottG

I know there have been several discussions on this topic. I've been perusing them, but as most popular subjects go, there is a wide scattering of opinions and options, so I'm kicking my specific questions out here.

When I removed my air conditioner I disconnected its outlet as it served no purpose. I'm now planning to reconnect it and use it to charge phones up on the valance when I have shore power. (The other two indoor outlets are not in convenient locations.)

This got me thinking that I might add a 12V outlet in the same location to use when I do not have shore power. Based on past discussions, my current thinking is to install a generic 12V "cigarette lighter" outlet and use it with a generic plug-in USB charger (same as I do in my vehicle). I would then run a dedicated wire back down to the converter area and splice it into the 12V circuit serving the existing outlet over the sink (and maybe also the lights--I haven't checked in a while).

So, are there better options than a generic 12V socket and plug-in charger? (USB outlets seem to get panned for their low amperage, phantom drain, and apparent lack of durability.)

Is there a better place to wire this in than the existing circuit I mentioned? (I would wire it in to the circuit for the former A/C vet fan, but that is switched and currently in use for something else.)

Thanks for any additional insights or advice. 

MuttonChops

If my project would do it the same way you have planned.
Both for components and wiring.

CrabTab

Perhaps something like this would suit your needs.  @ScottG

Amazon.com: Kohree 12V Marine Car Charger Socket Panel, 4 in 1 Waterproof Boat Cell Phone Rocker Switch Panel with 12 Volt Dual USB Power Outlet Cigarette Lighter Socket for RV Marine Boat Camper Truck Automotive: Home Audio & Theater

I used one to build a portable power supply. It has both USB and 12V lighter, it is switched (no parasitic drain when off), and has a meter to know basic state of charge for your battery.

ScottG

I like that, @CrabTab --thanks. I eyeballed some similar items but I particularly like the switch on that one, as well as the little voltmeter.

4ncar

@ScottG: I wired in a "cigarette" style 12V outlet  adjacent to the cargo door(inside) of my 320# for the purpose of my 12v fridge/freezer.  I tapped into the existing "charger outlet" circuit, for the ease of trouble shooting in the future( let's hope none).

mntrails

That 4 function panel is a great idea.  My Jensen stereo will come on intermittently and I have on the list, to put in a 12V power switch. I also have a 12V meter plugged in under the rear cabinets that's hard to read too.  I can do both those functions with this panel as well as get a couple more conveniently reached charging ports. Thanks for the link.

Sharon_is_SAM

@ ScottG- do you have an outlet centered along the rear shelf area?  On our CSS there was a 120v outlet and a USB.  We eliminated the USB on the build and they added a 12v under the edge of the rear shelf.

Dalehelman

@CrabTab.  Nice find.

ScottG

@Sharon_is_SAM, I have no additional 12V outlets other than the one mounted under the cabinet above the sink. It's a great location for my plug-in voltage meter, but not much else.

I think the back outlets were added the next year, largely in response to customer demand.

wolfeel2000

When installing this 12V outlet, where are you drawing your power?  I have run my wires to the power distribution center and cannot figure out the best circuit to tap into and the best way to do so.

4ncar

@wolfeel2000: I believe the blue wire on the 12 volt side is the 12volt charger circuit, you’ll need to confirm, unless I get to the trailer first. One you ID the wire these 1/2 taps are what you use to splice into the circuit.

https://www.amazon.com/OIIKI-Connectors-Connector-Solderless-Electrical/dp/B08GPZ2F4V/ref=pd_lpo_328_img_1/139-9599493-0857349?_encoding=UTF8&pd_rd_i=B08GPZ2F4V&pd_rd_r=f3ca983f-f606-4d98-819e-ec0b81f2108c&pd_rd_w=n0SaT&pd_rd_wg=u4Nk6&pf_rd_p=2eae1586-a44a-4b21-997a-1dfc1740e496&pf_rd_r=2SVHKAJCDEDMQCP6SGPG&psc=1&refRID=2SVHKAJCDEDMQCP6SGPG

ScottG

I'd also have to go out and confirm for certain, but Rick's 2016 electrical schematic agrees with @4ncar's assessment. Looks like the blue wire from the converter is a 10A circuit serving the lights, A/C ventilation fan, and 12V outlets.

Half-taps should work fine (nuCamp uses them all through the trailer) but I prefer properly crimped connections. I purchased a ratcheting crimper tool a few years ago and have never regretted it.

4ncar

Strip & crimp are great...solder even better.  The 1/2taps allow the less inclined to perform the connection.  In actuality, they are a "insulation displacement" connection.  They have a blade that cuts into the insulation and makes contact with the out edge of the conductor....where the electricity is(outer edge of conductor).  this type of connection is an industry standard for high speed data connections...its gotta be ok for for slow electrons! 🤣

Geo

The most important factor in using 1/2 taps is to use the correct wire gauge. Each tap should be labeled for the gauge of the wire it can be used on. Too small and it can cut the wire in two, too large and it will not penetrate the insulation to make contact with the wire.  As @ScottG stated Nucamp uses these for many connections, so do most RV builders.

JeffroNC

On our 2019 TAB400, I needed 12 volts for my CPAP adapter so I simply added a fuse to my distribution center in a spare slot. I connected a wire to it and I am all set.
Do you have any spare slots? 
PS I hate the Scotchlok connectors our trailers seem to be built from. As a former auto tech, I spent searching for bad connections which usually originated at one of these. 

ScottG

Good idea, @JeffroNC. I don't think I have any extra 12V fuse slots, but it's been so long since I've paid attention to that area I'm not sure. I'll have to give it look once it warms up enough to get out and work.

ScottG

Following up, I finally got around to this project and installed the panel recommended above by @CrabTab. I dropped two new wires down into the converter area and spliced them into the existing positive and negative leads for the lighting/charging circuit. It looks and works great!

BrianZ

Great idea to use that space on the cabinet, @ScottG!

CrabTab

Nice work @ScottG! Here is a pic of my install, to help others with 'imagineering'. I placed ours near the television (I know you don't use yours ScottG). We can keep our iPad charged while streaming or watching downloaded content. My spouse is making a bag to hang from the wooden frame to hold the iPad.



I also used one of the panels to make a portable power station.

wolfeel2000

@CrabTab:  I really like the portable power station.  What battery and box did you use to make it?

fstop32

@ScottG & @CrabTab I went with the same quad panel setup with the switch.  While waiting on Alde parts one of my mods was cleaning up the electrical closet and I went with a DIN rail which gave me multiple taps off the leads from the power converter without having to splice.  The jumpers inserted in the rail gave me multiple output connections for a given circuit, screw down connections for tinned wire leads.
I'm with you @JeffroNC on those Scotchlok connectors, when I was auto mechanizing my way through college those were the bane of my existence, plus they're just UGLY.

ScottG

I like that rail, @fstop32. It may inspire me to do something similar. When I installed the lines for the new panel I gave in and used the Scotchloks as the working space was a little tight for my cri@fstop32

Is that a false bottom installed over the floor of the compartment?

NoVaGuy

I am also looking into adding a 12v outlet to my 400BD.  I would like to mount the outlet under the Television on the angled panel.  The outlet would provide power to an antenna booster.  Where would be the best place to connect that outlet.  I would have a clear path to the battery, but not sure where would be best to make the connection.

Verna

@NoVaGuy, that angled wall in the 400 is just 3/4” plywood (the very expensive imported kind). What Austin’s group did for me in my former 400 was take the wiring snd coax up to the ceiling, around the corner, and went into the wire raceway through the bathroom to the converter. 

You could go low to the plywood under the bench on the driver’s side and take the wiring back to the converter. I cannot remember if there is another low wire chase under the bench….you’ll have to search for that. 

I would recommend the 12V plug under the bench as it would look neater with no wiring showing. 

CrabTab

wolfeel2000 said:

@CrabTab:  I really like the portable power station.  What battery and box did you use to make it?

Thanks @wolfeel2000.

The box is a .30 Caliber size (plastic) from Harbor Freight. 

0.30 Caliber Ammo Box (harborfreight.com)

The power comes from two 8Amp 12V batteries, wired in parallel.

Cabela's Rechargeable 12V Battery | Cabela's (cabelas.com)

Theoretical power is about 190 Watts. Output is comparable to the smaller size Yeti Goal Zero, albeit without some of the Yeti components (or cost). It was something I made for emergency recharging here in 'hurricane country'. I've made several for family and friends too.

CrabTab

Nice work @fstop32! That DOES look nice and clean.

My T@B, the Boondock Edge model, had an additional Blue Sea panel in the electrical compartment with three open slots. Lucky for me, I didn't have to do as much work as you. 

fstop32

@ScottG, yep, false floor.  There's some plumbing and wiring under it and I ran the wiring harness going to the back of the camper over the top of the wheel well.  The false floor sits on 3 blocks in the middle to support it held by screws into the blocks which are held to the vinyl by silicone caulk.  It's also supported at the outer edge of the bench box.  I can pop out the 3 screws and lift out the panel easily if I need to get to anything under it.
Here's a wider view.  I rebuilt the bench box and added a 3/4" plywood panel on the outside wall cut out for the wheel well so I could mount things to it and have a stronger support for the back edge of the bench seat.  We sleep on the twin bed idea so my seat top is made to slide out 3.5" so we have a slightly wider bed over it.  The cross support connected to the new outer plywood (notched for the GFCI) is wide enough to catch the seat plywood so it is fully supported when pulled out.

ScottG

Nice work, @fstop32. It looks like you have two 120V junction/receptacles in that space. What are those used for? (I'm guessing one might be the plug for the Alde.)

fstop32

@ScottG, just one.  The white one is the original GFCI that was in the mid-panel bench facing the cabin area.  I installed a quad box with a duplex outlet having 120v and 2 usb outlets.  The other half of the quad has 2 switches stacked and one controls half of the exterior duplex outlet (so I can turn lights on/off from inside) and the other is as yet undesignated.  I also installed a night light duplex to light the path to relief 
This pic is before I changed the base cabs to cherry veneer plywood.
The small blue box is just a junction box (now has a cover) because the 120v line was not long enough to lay neatly under the false floor so I had to lengthen it.  The Alde plug is still in the Alde closet.