What are these, wiring.

[miarosa]

Exactly!! Thanks, Eric. I'm going with some 12/3 awg triplex tinned copper marine wire (white,green,black). That'll take care of my outlets, and I have all new wires for lights, ect. I'm installing a converter, PD 4045, as I don't need anything too intense. This will allow for the lights to work off the battery, and give the option for an inverter later on if desired.

[Thomcat316]

Having grown up on boats (expensive fiberglass trailers with better waterproofing) it always terrifies me what passes for electrical in the RV world.

Don't use Romex, it's not meant to be used under vibration - use tinned boat cable instead. More expensive, once.

Same for wire nuts, and same reason - use crimp-type connectors with heat shrink insulation instead. Lever-type WAGO connectors are also vibration resistant, and make great junction blocks for things like lighting fixtures and fans.

Instead of a "licensed electrician", who is very competent in home/commercial wiring, seek a marine electrician. RV and boat wiring are almost identical, while residential/commercial electric typically has no low voltage wiring. RV/marine is predominantly 12V DC, with considerations that never impact your average licensed electrician.

Also, for the DIY inclined, Blue Sea Systems has a great ampacity chart. Use the 3% column, not the 10% column - it will help your batteries last longer. Blue Sea Systems also makes great 12V and 110V breaker panels and fuse blocks - very expensive, but designed for the marine environment. They will hold up well in the RV environment also.

[miarosa]

Thank you! That is indeed what we are doing- luckily we live in a beach area.

[Raspy]

Originally Posted by Thomcat316

Having grown up on boats (expensive fiberglass trailers with better waterproofing) it always terrifies me what passes for electrical in the RV world.

Don't use Romex, it's not meant to be used under vibration - use tinned boat cable instead. More expensive, once.

Same for wire nuts, and same reason - use crimp-type connectors with heat shrink insulation instead. Lever-type WAGO connectors are also vibration resistant, and make great junction blocks for things like lighting fixtures and fans.

Instead of a "licensed electrician", who is very competent in home/commercial wiring, seek a marine electrician. RV and boat wiring are almost identical, while residential/commercial electric typically has no low voltage wiring. RV/marine is predominantly 12V DC, with considerations that never impact your average licensed electrician.

Also, for the DIY inclined, Blue Sea Systems has a great ampacity chart. Use the 3% column, not the 10% column - it will help your batteries last longer. Blue Sea Systems also makes great 12V and 110V breaker panels and fuse blocks - very expensive, but designed for the marine environment. They will hold up well in the RV environment also.

Great post. Thanks.

[gordon2]

Originally Posted by Thomcat316

...
Don't use Romex, it's not meant to be used under vibration - use tinned boat cable instead. More expensive, once.......

I have never seem a report of Romex, or any non-metallic sheathed cable, failing in a camping trailer. At least not if the cable is secured.

I have seen quite a few reports of the connections where NM cable is used failing, such as at the connection to circuit breakers or ground busses.

The argument against using solid core wire in a trailer seems to be based on the danger or the wire flexing due to vibration to the point that it is weakened and breaks. But I have never heard of that happening.

The vibrations do seem to loosen connections however, and there are far too many reports of power panels, etc. overheating due to loose connections with high resistance and / or arcing.

So my question is:
Does "tinned boat cable" help to prevent connections at breakers and the like from becoming a problem? If so, how?

(PS.. in general I think you make some great points.. treat a FBRV as a boat and you will spend a little more money up front but be much happier in the long run.)

[LeftToaster]

I agree that you shouldn't use Romex (NM or NMD) in RVs. It is rated for 600V and temperature range of -10C to 90C but solid conductors and a stiff PVC jacket transfer any vibration to the terminations. Additionally, with the large temperature swings that an RV sees compared to internal residential wiring, thermal expansion of the conductors could further loosen standard wire nuts (which are also not suitable for vibration). If you do have Romex wiring, crimp on or set screw splices / wire nuts should be used at a minimum.

There are better options:

Service cable (AKA Cab Tire) - SOOW, SJOOW, SEOOW and SJEOOW. Basically rubber (or elastomer in the case of the E cables) coated, flexible, water/weather resistant, oil resistant, stranded electrical cord. The SOOW and SEOOW are thick, heavy duty and 600V rated while the J (junior) variants are thinner and 300V rated. The E variant has better chemical resistance and is rated to -50C vs -40C.

Marine Triplex (Ancor Triplex) - is also stranded and weather, chemical and vibration resistant, but it has tinned (solder coated) wires to resist marine corrosion and a stiffer PVC jacket (rated to -20C to- 105C). Generally RVs don't experience the corrosive sea water environment that boats do. It has a less flexible PVC jacket and comes in round or flat profiles. It is similar in price to SJOOW.

I would use SJOOW or marine Triplex for internal circuits and SOOW for your shore power cord.