Wiring Diagrams for 30A/50A RV Recepticals?

[AIRHEDS]

Does anyone have the correct/complete wiring diagrams for adding 30A and a 50A RV receptacles? Maybe even the correct quality parts to order? We frequently see the same questions and the same warnings but I don’t recall seeing a prescriptive “give this diagram to your electrician...” response. Has anyone got something good to share? The answer will benefit “The U7” OP in http://www.airforums.com/forums/f37/...ie-182073.html. I’d have posted there but didn’t want to hijack his thread. Thanks for all of us that can use this info! Regards...

[rmkrum]

The 30 amp receptacle I picked up at the big box home improvement store was marked RV-30. The diagram was on the inside of the box. It is straightforward if you understand household wiring and have room in the panel.

I’d suspect the same thing for the other version.

If you hand it to an electrician be doubly sure he understands an RV-30 is for 120 volts single phase 30 amps only.

They tend to screw this up...and think it’s a weird dryer outlet, wire it for 220 volts, and blow electrical stuff out in your Airstream!

[garry]

everything you want to know



http://www.myrv.us/electric/

[uncle_bob]

Hi

The key point is that the 30A plug should never be wired for 240V and the 50A plug always gets hooked to a 240V source. Indeed there is a bit more to it, but those are the basics.

Bob

[A W Warn]

Originally Posted by AIRHEDS

Does anyone have the correct/complete wiring diagrams for adding 30A and a 50A RV receptacles? Maybe even the correct quality parts to order? We frequently see the same questions and the same warnings but I don’t recall seeing a prescriptive “give this diagram to your electrician...” response. Has anyone got something good to share? The answer will benefit “The U7” OP in http://www.airforums.com/forums/f37/...ie-182073.html. I’d have posted there but didn’t want to hijack his thread. Thanks for all of us that can use this info! Regards...

This website explains how to wire a 30 amp 120v outlet. It also explains why and how the mistake is often made that it is connected to 240v, and damages RVs.

http://noshockzone.org/accidentally-...0-volt-outlet/

When an RV outlet is purchased there are wiring diagrams either on the box it comes in or on a pamphlet inside the box.
The receptacle itself has marking designating which wire should be connected to each terminal.
The problem: it looks so familiar the instructions are overlooked. Even a qualified electrician can make a mistake.

Add edit: parts
30 amp 120v receptacle - NEMA TT-30 (not twist lock) - this is the one that get's wired incorrectly
30 amp 120v receptacle - NEMA ??? (I don't know twist lock #)
50 amp 240v receptacle - NEMA 14-50R

Add edit 2:
The most economical way, and probably the quick/safe way, is to get a pre assembled load center with all the breakers and receptacles already installed. Google "RV 30 and 50 amp Load Center" .
This is one example>
https://www.amazon.com/dp/B00A8FQUYW...a-319132207842

[Mollysdad]

May I ask the goal?
Is it to replace a 30 amp connection with a 50 amp?
If so, there's a lot more to it than replacing the receptacle.
If you just want to see how the plugs are wired, there's lots of diagrams available.

Do you want to add a 30 and 50 amp receptacle to your house?
or to your RV?

[AIRHEDS]

Thanks for your responses so far. The reason for my asking the question is two-fold:

- First, because I’m interested in adding a 50A RV receptacle to my home so that I can connect my 50A trailer to power when it’s on the driveway. We’re building a house now and it won’t be ready for us to move in until Sep/Oct, so there’s no rush.

- Second, because I thought this would be helpful information for others with the same question for the reasons I wrote in my original post: I hadn’t seen a post saying, “Give this diagram to your electrician.” I haven’t looked at the links you’ve provided yet but I surely will shortly. I’ll likely do the wiring myself.

Again, many thanks! Sincerely, Rich

[rmkrum]

Originally Posted by AIRHEDS

Thanks for your responses so far. The reason for my asking the question is two-fold:

- First, because I’m interested in adding a 50A RV receptacle to my home so that I can connect my 50A trailer to power when it’s on the driveway. We’re building a house now and it won’t be ready for us to move in until Sep/Oct, so there’s no rush.

- Second, because I thought this would be helpful information for others with the same question for the reasons I wrote in my original post: I hadn’t seen a post saying, “Give this diagram to your electrician.” I haven’t looked at the links you’ve provided yet but I surely will shortly. I’ll likely do the wiring myself.

Again, many thanks! Sincerely, Rich

OK, a DIY'er after my own heart..a few considerations before you haul off and start buying parts:

1. Consider location of the trailer vs the outlet box. Needs to be close enough to reach with the trailer power cord.

2. That leads to the distance to your utility panel, which needs a reasonable rout to get some very heavy cables to it. The distance will determine the cable gauge and how you need to protect it.

3. There needs to be a way to get into your power and breaker box, and you need room to install TWO single-pole breakers with a bridge connecting the handles. You also need room in the ground/neutral buss bar to tie down both the neutral (usually white) and the ground (safety earth) wire, usually bare copper or aluminum.

4. You need sufficient capacity in your electrical panel to power all this stuff. Depends on what you already have in there, and how heavy the loads are on your house, then enough excess capacity to handle a trailer...

5. You need to consider how hard it will be to get to the RV connection box from the breaker panel. If the RV gets parked right outside your meter panel, hey, presto--it's super easy to run the cable between the two. If it's all the way across the house, getting into the area the cable or conduit has to run can be interesting. (Especially if you are bulky, and getting a bit arthritic...like me).

6. If it's a long run, it is going to take another set of hands to do it--cable is stiff, and will need both push and pull to get it in place.

Yes, it can be done DIY. I do 30 amp all the time. In my son's house, the meter and panel are right next to the RV slot. On the other home, where I really want to park the RV, the meter is on the other side of the house. That one, even for 30 amp, is going to be a royal pain to get it from the panel in the garage, half-way across the house, in an area I can't get my butt into easily. I'm going to have to pay a skinny helper to pull this one off.

Scope it all out, estimate distances, look up proper wire sizes, and, if it makes sense, go for it. Most jurisdictions allow homeowners to make "electrical repairs", but make sure you do not need an inspection or permits, ore are required to use a licensed electrician....

Laws vary widely...and you don't want the house to burn down and have your insurance stiff you just because you ran a new circuit without permits and inspections...be careful and do it right...

[AIRHEDS]

Thanks for all once again—completely understood. I will double check on the requirement for a licensed electrician to do the work when I pull the permit; it’s a foregone conclusion that I’d have it inspected after completing the work. I am having 400A service installed to the house and once we move in, I’ll likely break-out 100A to a sub-panel for my shop that includes this outlet. I’ll also ensure I’ve got sufficient gauge for current and distance between the box and the outlet. I won’t even make any jokes about how much voltage I should see between ground and neutral. :-). Thanks again, Rich

[Mollysdad]

Originally Posted by AIRHEDS

First, because I’m interested in adding a 50A RV receptacle to my home so that I can connect my 50A trailer to power when it’s on the driveway. We’re building a house now and it won’t be ready for us to move in until Sep/Oct, so there’s no rush.

Perfect!
The good news is that a 50 amp connection like used in an RV is exactly like a receptacle for a electric stove that runs on 240v.

The reason it doesn't damage anything in your trailer (if correct) is that your trailer never uses both legs of 120 together. So you have (2) 50 amp 120v circuits.
You will have two hots (one red and one black) a neutral (white)
and a ground (green). You'll see the white neutral and the green ground go to the same buss bar in the breaker panel, this is normal.
I'm not the one who can advise what gauge wire to run over a distance, but it will be fairly large.
You will add a 50 or 60 amp breaker made for 220 (the levers are joined) into two slots of your breaker panel. Connect the red to one side and the black to the other BEFORE pushing it into the bus bar. (Or cut the main breaker)

Easy.
But if you're squeamish about looking at voltage, an electrician can do it in 15 minutes under $100

[AIRHEDS]

Outstanding! Thank you MollysDad. I don’t care too much for aluminum ... ahem ... “aluminum wires” ... the need for noalox makes me nervous. I’d rather go old school and pay for copper. But again, I’ll research the code requirements, double-plan and triple-check whatever I decide to do. Thanks again to all for your responses and info!

[rmkrum]

With proper sized cable, noalox on the ends, breakers and receptacle rated for aluminum wire, it’s a non-issue. Heavy industrial stuff is typically wired with aluminum because it’s much cheaper.

I agree, copper seems safer, but you will see your electrician use proper aluminum on main service, electric stoves, and sub panels. Al long as you see a coat of gray noalox and properly tightened fasteners you are good to go. It’s all covered in the code.

[uncle_bob]

Hi

Aluminum for the wire to the box ... not a big deal. Aluminum for the cable to your trailer ... not a good idea. You *do* see copper plated aluminum wire coming out of China. It gets used in jumper cables. They are the ones that don't last as long ...

Bob

[A W Warn]

There is a possible error in the wiring diagram in post #10. (since the wire feeding the panel is not shown)
The green/ground and white/neutral are going to the same terminal bar in the distribution panel. Ground and neutral can be bonded that way only in a primary panel. (if you have a secondary panel in your garage as you stated in post #9, it should not be wired this way)

If that illustration happened to be inside a secondary panel the ground and neutral should not bonded. In a secondary panel the ground would connect to a grounding bar mounted directly to the case, and the white wire would connect to the neutral bar as shown, and the bonding screw (connects the case and neutral bar) would be removed from the panel (if there is a bonding screw installed)

[A W Warn]

Square D provides this video about the bonding screw
Pay special attention to the statement about the bonding screw should only be used in the main distribution panel.

https://www.youtube.com/watch?v=6HGaRNBcADY

[rmkrum]

Sometimes its a bonding screw, I have seen other boxes with a bonding bar or strap run between the ground buss and the neutral buss. The neutral buss is insulated from the box in sub-panels, as you suggest...

The only tie between Neutral and ground should be in the entrance panel, and there should also be a connection from it to the building steel, a driven ground rod with at least 8 feet in the ground, or a "Eufer ground" which connects to at least 20 feet of rebar buried in the concrete foundation directly to the entrance panel ground bar...

In any case, the wiring must be done in FULL accordance with the NEC, or locally enforced and inspected variants of it...

[AIRHEDS]

I love this forum. Thank you all!