Where should I wire my 12volt Outlet into?

Discussion in 'Wiring' started by mpking, Jul 7, 2018.

  1. mpking

    mpking Well-Known Member

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    Raynham, MA
    So I'm wiring an external 12 volt outlet.

    I've already selected the location, and drilled the hole. Now I'm attempting to figure out where to connect it. The device I'm connecting draws (surge) 8 Amps.

    It's located at the very front of the curbside (passenger side) of the camper. From here it's equidistant to the converter and to the battery. I will have to run on the underside of the camper, if it matters to anyone.
    • My initial thought is wire it into the converter, but the Converter I have is very old, and the wiring is a rat's nest. (Wirenuts and black tape everywhere) I'm concerned I might make a bigger project if I touch it.
    • Next thought is run it direct to the battery. It would still be powered if I'm on shore-power. But it does make the battery connections a little more complicated (two sets of wires), plus I'd have to fit a fuse in there somewhere.
    • Last thought, run it to the existing fridge, and tap the power there. I'm kinda favoring this, as it's fused off the existing 15amp circuit, and the fridge already has 10 gauge wiring.
    Thoughts? Other idea's I haven't covered?
     
  2. Raycfe

    Raycfe Waterford Ct.

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    I had a camper that it put an outlet in the refrigerator compartment. I used it for my tire air compressor.
     
  3. nineoaks2004

    nineoaks2004 Every meal is a picnic and every Day is a holiday

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    • Reefer is probably the best bet. just make sure you fuse whatever it is you are going to run and the fuse should be smaller than the reefer fuse.
     
  4. roybraddy

    roybraddy Well-Known Member

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    When i got my 2008 Starcraft 14RT trailer I knew right away I was going to have to redo the 12VDC Distribution setup. My unit had four zones for 12VDC and ever thing was tied into this using the large YELLOW twist on connectors... All of this wiring was located in an open area behind the ELIXIR Converter/Charger single mode 13.6VDC 30AMP DC system. Looked like a rats nest of wiring hehe...

    I knew I would be planning on keeping this really nice OFF-ROAD RT14 Popup Trailer for many years so I changed out this older Power Distribution setup system for a more modern 120VAC AC/12VDC Power Distribution panel that had five large size 120VAC Circuit Breaker slots, Eleven ATC 12VDC Fuse locations as well as two ATC special fuse locations for REVERSE POLARITY connections... This was a WFCO 8900 series Power Distribution Panel that replaced the older ELIXIR 30A Power Distribution system.
    [​IMG]

    This was a pretty easy mod to do as all of the wiring was already routed to this this same area and really only took around two hours to change the ELIXIR system out for the WFCO 8700 Distribution setup... I also upgraded to a multiple DC Voltage Smart mode Converter/Charger using smart mode technology to operate my planned upgraded Battery bank.

    On the 12VDC side I have plenty of ATC fuse positions to use for various new connections.

    On the 120VAC AC Side I have positions for one large slot for the Main 30AMP Circuit breaker and then the remaining four large breaker slot I have Eight each 1/2 size 120VAC breakers for my expanding 120VAC Power Distribution...

    This was all done back in 2008 and today i am still expanding the 12VDC Power Distribution panel by installing another BLUE SEA 12VDC Fuse Distribution panel... Being a Ham Radio guy I am always adding something hehe...

    [​IMG]

    I have also added a few four position BUS BAR for direct connections to the batteries as needed. This keep the battery terminals not having more than two connections at a single terminal...


    [​IMG]

    Blue Sea also make stand along fuse positions as well that uses the 5/16-inch lug connections...
    [​IMG]
    [​IMG]

    This is great for all of my 12VDC cables using 5/16-inch ring terminals...

    My problem is this is what I did for a living in my Naval Electronic Systems working years so it all continued on with my Electronics Hobbies in my later years... Sort of follows the rules if you are going to do it - then do it half way right haha...

    My favorite wiring cable was what they call BOAT CABLE which is two wire cables inside a nice weatherproofed sleeve. My wiring size was both 12GAUGE and 14 Gauge wiring using RED and BLACK wires or WHITE and BLACK wires keeping with the standard 12VDC wiring scheme with RV trailers.
    [​IMG]


    Not saying you have to do all of this just passing along what I did to solve where I was going to make additions to my 12VDC Distribution. I did similar things on the 120VAC side as well...

    Roy Ken
    [​IMG]
     
    MichiganCur likes this.
  5. jnc

    jnc Welcome from New Hampshire

    I like the idea of running direct to the battery just to keep it simple.
     
  6. mstrbill

    mstrbill Active Member

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    What kind of outlet are you using? 8 A may a too high for a normal cigarette lighter style.
     
  7. mpking

    mpking Well-Known Member

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  8. tenttrailer

    tenttrailer Art & Joyce - Columbus, O

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    I would run to existing wiring that has a least a 10 amp fuse on the wiring to support the 8 surg amp draw. I like the idea of the 12v on the fridge, because you normally are not running the fridge on 12v when when using other things in the campe. You normally only run it on 12V when traveling? also the fridge 12v wire should be rated for 10+ amps.
     
  9. SteveP

    SteveP Well-Known Member

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    Agree.
     
  10. mpking

    mpking Well-Known Member

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    Raynham, MA
    This is to run my 12volt compressor cooler. This will be *instead* of the propane Fridge. (I have a whole thread on this. Short story, the Propane one does not work)

    Here's the final mounting location:
    upload_2018-7-8_15-23-33.png

    Here's a close up:
    upload_2018-7-8_15-24-7.png

    The Dicor got a little messy from my first failed attempt at mounting. (The wall was thicker than the panel mount, I had to bust out a bunch of the inside wall paneling to get enough room to turn the screw to compress the panel mount.

    When it dries, i'll rub it off the rubber. (If I can)

    I'm happy. It's tied into the Fridge. It's 10 gauge wire all the way thru (Outlet to the converter, converter to the battery)
     
    jnc and Raycfe like this.
  11. mpking

    mpking Well-Known Member

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    Raynham, MA
    So.......

    Apparently It's not 10Gauge all the way thru after all.

    While test driving it in my driveway, the compressor on the cooler kept shutting off. I launched the app to pull up the diagnostic screen. When it was kicking on, the voltage on the battery would drop to 9-10 volts. This will trigger the low voltage shutdown. :-(

    Battery was reading 12.4 volts at the battery.

    I rig a temporary wiring job directly off the battery, and compressor reports 12.4 volts and works fine. (No fuses, so this was only to prove a point, it's already off the camper)

    So somewhere in the original wiring harness, the wiring drops to a small enough gauge that the voltage drop is pretty severe.

    I guess I'm going with Secret Option D:
    • Use some of the stuff that Roy recommended, and Built some kind of Bus Bar distribution off the battery.

    Now I need to plan it out, with proper fuse protection. I was planning on relocating on the battery about 6 inches to fit a group 27. Guess that project got bubbled up to the top of the list.

    I'm liking the power center, but since it's on the tongue, I'll have to find something small enough to fit in a 6 x 6 waterproof electrical box.

    I'm liking this one. Small 2x3x2(ish). Waterproof. Lights up when the fuse blows.

    https://www.amazon.com/dp/B074XYY96...&pd_rd_r=f6b1fa84-857f-11e8-906c-89fc5d574e42
     
  12. mpking

    mpking Well-Known Member

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    Looking for some opinions.
    I'd have to buy the Circuit Breaker (which doubles as a power disconnect) ($21.99)
    https://www.amazon.com/dp/B07D7T3ZR...colid=VP6N437JV225&psc=0&ref_=lv_ov_lig_dp_it
    The bus box I'd get the one with the cover ($12.99)
    https://www.amazon.com/dp/B074XYY96...colid=VP6N437JV225&psc=0&ref_=lv_ov_lig_dp_it
    Bunch of forked crimped connectors (I'll have to find some on amazon, local auto parts store seems to have crap for selection)
    I think I have to get a waterproof plastic 6x6 electrical box. The Bus bar is waterproof, but the main power lug is exposed.

    This would significantly clean up the wiring connection on the tongue.

    Thoughts?

    upload_2018-7-12_21-45-6.png
     
  13. mpking

    mpking Well-Known Member

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    Raynham, MA
    While inspecting things today, making plans for what I need to order, I noticed the Negative terminal lead from the battery to the trailer frame must have been replaced, and whoever did it looks like they used either 14 or 16 gauge wire. (Maybe even 18, but I don't think so)

    So before I spend around $100 dollars and hours of time redoing everything......

    Would 2 feet of 16 gauge wire at the end of 20 feet of 8 gauge wire, drop the voltage 2.5 volts? (from 12.4 to 9.9)

    @roybraddy You should be able to answer that.. :)

    Figured I'd ask, since I don't have time to mess with it this weekend and see if it fixes it.
     
  14. roybraddy

    roybraddy Well-Known Member

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    King George, Virginia
    Well I certainly don't have all of the answers but when I added additional batteries to my setup I also rewired the planned high current 12VDC cable paths using 4 AWG cables... Just beefing up the cables from the NEGATIVE side to frame will not hurt but will not totally solve your listed problem. You can melt down the cables on the Positive side battery terminal as well using too small gauge wire.

    It would bother me big time to see 12.4VDC drop down to 9.9VDC when something was turned on... That's when it always got dark on me around 10PM at night... If you measure 12.4VDC at one end and 9.9VDC at the other end than that would be cable loss. But if both ends dropped down to 9.9VDC when you hooked up that circuit would be the battery is losing its charge problem or not strong enough for the load being used....

    This is where one of those CRAFTSMAN (SEARS) AC/DC 400AMP Clamp on Current meters will come in handy. You can clamp around ONE CABLE and monitor what it is doing current wise...

    All of my cable wiring around the battery connections for multiple batteries are 4AWG wiring as well as the main wiring going to my Blue Sea Selector 12VDC switches and the 12V DC Power Distribution Panel. Most of the individual 12VDC circuits I have coming off the 12VDC Distribution are 14-12 gauge BOAT CABLE wiring. If a large DC current Device is planning on being used it should go directly to a separate BUSS strip using 5/16-inch lugs or on one of those BLUE SEE SWITCHES terminals using 4AWG wiring going directly to the battery terminals... My rule of thumb is to never add more than two 5/16-inch ring terminals on one lug connection. I guess you can say any wiring that is using the 5/16-inch ring terminals should be be using 4AWG size cables...

    If you know the DC Current being used and the size of the cables there is plenty lists on-line showing what the DC Voltage will be... You don't want to see any DC Voltage Drop as that relates to heating up wires and connectors and will eventually burn up those connections.

    I like having most of my wiring at the 12-gauge size with perhaps a few that have already been run at the 14 Gauge. Any of the other higher DC Current items that I plan on using should be 4AWG size. Others may want to use 2AWG size cables...

    Just keep in mind that all of your smaller size gauge wires that are pulling DC current will add up big for the one common battery cable that is going to the frame ground.

    Not having enough time before your upcoming trip to get all fixed up proper could work ok for you but you must have a way to watch the battery lines to be sure you are NOT out of specs for things. Will have to watch every close when being used.... Feel lines for no abnormal heat being generated etc...

    Not fun breaking down many miles away from local sources like LOWES and WALMART to fix things...

    Once you start having problems than you will start adding your Truck Start battery to the picture and then guess what - it goes bad on you and you are stranded now haha... Thats my other golden rule - Never mess with my truck start battery... It has one function only and that is to run the truck 12VDC requirements and start the truck engine... Only way to get back home with all your goodies hehe...

    Roy Ken
    [​IMG]
     
  15. mpking

    mpking Well-Known Member

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    Raynham, MA
    I had a chance to fold up the camper today (I've had it open for the last month while making modifications and adjustments), and get to the wiring on the tongue.

    I replaced that 2 foot section from the battery to the frame with a 10 gauge wire. It was definitely 16 AWG wire. The wire from the convert to the frame appears much larger, might be 4 AWG.

    The voltage drop went from 9.9 to 10.6 (Measured at the battery was 12.6). So while better, not good enough.

    I'll have to continue with my plan of putting a wiring center on the tongue.
     
  16. SteveP

    SteveP Well-Known Member

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    Had a similar problem with my small fridge during my last dry camp. Never happened before but highs were in the high 90s with a couple of days in triple digits. I was using an expensive SeaDog all stainless steel outlet rated for 15 amps. In the afternoons the compressor would shut off. I know it was voltage drop due to the heat because when I got up the next morning the fridge was running fine.

    I changed the cig plug out with Anderson connectors and shortened the power cord to about 1/2 the original length. Testing with the new CFX, before I changed the plug I was seeing almost 2 volts drop by the app, after the change it's about .5 volt. No other changes to the circuit. I think that much drop is reasonable considering the amps the compressor pulls on startup. You'd probably get similar results using a Zamp outlet and an SAE two wire plug.

    If i were you I'd run 10 gauge wire directly from the battery to the outlet, bypassing the camper circuits. Fuse the wire at the battery at 10 or 15 amps. Run the ground from the plug directly to the frame below it, also 10 gauge. And change out the plug.
     

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