I want to install a 50amp RV pedastal. Run will be about 30 feet from the breaker box to the pedastal. I have on hand an ample supply of Nr. 4 AWG wire. I know this is overkill; however I have the wire on hand. Is there any reason I cannot or should not do this?GM

Sounds good to me. As long as you understand how and wire it correctly for an RV 30 feet is nothing.

If undergound, wire needs to be THWN rated to meet code requirements.

sgip2000 wrote:If undergound, wire needs to be THWN rated to meet code requirements.More precisely, if in conduit it needs to be wet location listed and if not it needs to be listed for direct burial. THWN is most commonly what would be used in conduit in this situation, but it's not the only permitted option.

How are you going to terminate #4 onto the 50 amp recept. terminals? You probably need to splice #4 to a smaller gauge at the recept. to make it work. If so, the splices will be physically large and require a large junction box adjacent to the 50 amp recept. Same at your panel. I think you'll need split lugs to do this. Before you use the #4 you might want to price out the lugs and junction boxes vs buying some new wire.Absolutely no reason not to use the #4 wire, except as above and also as noted by another poster above, the insulation jacket on the wire must be code approved for the location and application.

50 Amp Pedastal/Nr. 4 AWG | Good Sam Community

18 Replies

sgip2000
Explorer
Jun 18, 2018
DrewE wrote:
sgip2000 wrote:
If undergound, wire needs to be THWN rated to meet code requirements.

More precisely, if in conduit it needs to be wet location listed and if not it needs to be listed for direct burial. THWN is most commonly what would be used in conduit in this situation, but it's not the only permitted option.

You are correct. I should have been more specific.
MrWizard
Moderator
Jun 18, 2018
#8 40 amps
#6 50 amps
Grey_Mountain
Explorer
Jun 18, 2018
OK. Nr. 6.
When working on a housing addition, my son-in-law came across a partial spool of Nr. 2 and gave it to me. Not a lot of need for it here. I used it to run from the pole to the breaker box in my shop.

GM
wnjj
Explorer II
Jun 17, 2018
ScottG wrote:
Grey Mountain wrote:
Run will be inside from the breaker to a location on the wall of my shop. I have 200amp service in the shop. Short run(one foot) through the wall to the outside receptacle.
Just checked - the wire I have is Nr. 2. Way overkill. Will just buy enough 8 AWG to do the job.

Thanks for the information.

GM

8 awg is too small. Use the 4 awg.

He has #2. I'd just buy some new #6.
ScottG
Nomad
Jun 17, 2018
Grey Mountain wrote:
Run will be inside from the breaker to a location on the wall of my shop. I have 200amp service in the shop. Short run(one foot) through the wall to the outside receptacle.
Just checked - the wire I have is Nr. 2. Way overkill. Will just buy enough 8 AWG to do the job.

Thanks for the information.

GM

8 awg is too small. Use the 4 awg.
wa8yxm
Explorer III
Jun 17, 2018
Grey Mountain wrote:
I know this is overkill; however I have the wire on hand. Is there any reason I cannot or should not do this?

GM

Short answer: NO. no reason at all not to do it that way.

Long answerL Generally when it comes to wires that carry current.. OVERKILL is a good thing. So go ahead and do it. I mean the only reason not to is COST and you already have the wire so GO 4(Ga) IT.
Grey_Mountain
Explorer
Jun 17, 2018
Run will be inside from the breaker to a location on the wall of my shop. I have 200amp service in the shop. Short run(one foot) through the wall to the outside receptacle.
Just checked - the wire I have is Nr. 2. Way overkill. Will just buy enough 8 AWG to do the job.

Thanks for the information.

GM
MrWizard
Moderator
Jun 17, 2018
no problem with using 4ga wire

just use the appropriate conduit and connections etc..
DrewE
Explorer II
Jun 17, 2018
MEXICOWANDERER wrote:
Number of conductors AWG into a certain size raceway:

Is there an online reference now for underground wire vs conduit diameter?

The NEC is available online in all its glory if you sign up for access from the NFPA. It's not the easiest to get to nor the most convenient to read they way they have it set up (they'd really prefer you pony up to buy a copy, after all), but it is there. Here's a link to get started.

It's been awhile since I looked at it, but as I recall conduit fill factors were not just a table and done. It varied some based on the type of wire (multiconductor cable vs. individual wires, etc.), their application (current carrying vs. safety ground, etc.), and maybe a few other things. I don't recall offhand that conduit location, whether buried or not, entered into the question.

As a practical matter, particularly where you are and the NEC doesn't apply or at least isn't enforced, I'd think eyeballing things such that the wires comfortably fit and could be pulled without undue trouble would be sufficient.
ScottG
Nomad
Jun 17, 2018
MEXICOWANDERER wrote:
Number of conductors AWG into a certain size raceway:

Is there an online reference now for underground wire vs conduit diameter?

There are NEC guidlelines that one can Google.