What gauge wire do I need?

[b1mmuo27]

Sorry I have to say this, where is all the bad information coming from? I am a licensed electrician for the past 33 years. Its called DC because it travel one way, direct current. Never heard of this x 2. Running LED lights? #8 is good for 50 amps. Amps is amps, volts are volts. The idea of a loss over this small distance is negligible.

[labracorn]

I don't where all this is coming from,there is no wiring bigger than#14 for 12v lighting in your unit.

[b1mmuo27]

Yes you can buy a piece of #8 R90 in black & white. Plus a bare piece of ground #10. Tape them together or place them in a piece of split plastic wrap. A fuse only needs to be on the black wire at one end. The wire you should be able to purchase at the Home Depot or any electrical supply. I'll take a picture of mine. I rewired it with a new converter & 12DC panel. You will be good for 50 amps free air rating. If you are running from one panel to another. Other than that labracorn said it.

[andrewjsmith]

Hey guys, sorry for all these questions. I'm just trying to do this once, do it right and do it without drilling unnecessary holes in my new trailer. I'm not at my trailer right now, nor have I taken any exact measurements. The two options I see for myself are: 1) run 6 AWG from battery to rear compartment, or 2) run 8 AWG from battery to under the dinette seat. The dintete route is a shorter run and more centralized on the trailer. It would be easier to run either direction from there.

If I run all the way to rear compartment, I can follow the factory wiring up to the fuse panel and then fish the wire under the sink, toilet and shower into back compartment. No drilling. Obviously that means any lights I install in front compartment means I have to run wire all the way back up front.

I'm using Blue Seas 5025 fuse block. I'm not sure I feel comfortable with trying to tap into the factory fuse distribution panel. At best there would only be one open spot to use? Not sure if it's safe to come off that into a fuse block and run multiple other power draws from there.

Could I run a jumper off the existing panel to power the new fuse block? Wiring would be way easier and I would still get 110v power or 12v power.

Thougths?

[eldermike]

IMHO: Run 8-2 from the battery to your new block location, use a single fuse (fast blow Maxi-ATC-50) on the positive very close to the battery and you are done with the block wiring. From there your lights can be run with any good quality automotive wire in say 14 gage. You can use a chassis grounding on the light runs even though you have a discrete ground wire on the block, a ground is a ground and led's don't care much about voltage drop they have a voltage range.

[Mustang65]

Originally Posted by andrewjsmith

So I'm going to install an auxillary fuse block in a storage compartment in the trailer for LED lights and anything else down the road.

Marine Wire 8/2 AWG Gauge Size Flat Duplex 8 AWG 2 Conductor Boat Cable Genuinedealz.com

Trailer is a 2015 SLX 264BHW.

b1mmuo27 ... Let's go back to post #1, see above quote. The LED lights are not the issue here, it is the anything else down the road. that raised the RED flag. So, since there is no indication as to what "anything else" happens to be, I suggested that they use the cable charts to plan on what they might want to use as a max amperage capacity for the line feeding the rear of the trailer.

I had a person ask me if it is ok to run 12AWG romex (house wire) from the battery to the rear of their 38 foot trailer, where the media center was, so that he could plug in a few things.. after digging deeper, he wanted to plug in a 600watt inverter to run his TV, then in another response he wanted to plug in his DISH receiver and external recorder. The 600 watts on the 120VAC side did not sound like much to him, but I informed him that his 250-300 watt TV alone would need 20 to 25 amps and add on another 5 amps for the receiver and recorder he was up to 30 amps (of continuous loading), coming from the battery (only had one 85Ah battery).

As an electrician, you know how people think that you can just plug anything into an outlet without thinking about it. Here at JOF, the GREAT thing is that members ASK for the opinions of others. Most replies will be on the conservative side and on the side of safety. I would not want to offer an opinion that would put a fellow member and his family in any kind of jeopardy, so I error on the side of safety.

As for running a pair of wires, take a look at the ground/frame connection on your TT. Mine was a #10 screw that was tapped into the frame (rusted around the hole) with a washer and a 8AWG ground wire from the battery. The lug was oxidized, so I am not sure adding 30 amps to the frame anywhere would have been a good idea, as there would have been a lot of heat generated at that point.

Granted 18AWG is overkill for the LEDS, but it is about anything else down the road that is the topic for me.

As I say... use the charts and build in a buffer for future use.

Just my thoughts,

Don

[andrewjsmith]

I really appreciate everyone's input. It's been a few years since I did any 12v wiring and I'm new to RVing so some aspects of it are new to me. In all honesty, I don't plan on adding much else. I was only doing this route because I have no clue how to tap into the existing panel.

[jamoke]

Try this wire size calculator on the blueseas website.

Circuit Wizard - Blue Sea Systems

I've used this with success in re-wiring my boat. DC wiring in an RV is similar to marine DC distribution.