Electrical Question

Obanion

Any advice that anyone could give me would be much appreciated.

You are OK so far. Depending on how your local code is you might have to put in a ground stake close to the RV box. You will have to run 3 # 10s to the main panel. If it is any distance at all I would make it three conductor # 8 and all of it in an underground PVC conduit. And I would leave the receptacle and the box grounded together. While you are at it I would also run a cable TV and a phone wire. Bob AZ

Be sure to call your trenching call center before you start. I just replaced my pool circuit, 20 years old and it rusted apart under the kool deck. I already knew where everything was but if you hit something your going to pay for it unless you call first. Once that is done you could just buy some UF cable, as long as it is protected by conduit once exposed. Uf is designed for underground use. It is a bear to strip and terminate but quite useable.

Will allow you to figure out the voltage drop based on the distance. Based on a 30 amp load, starting loads etc, your run should be less than 80 feet or your going to need larger wire.

Connect the ground conductor to the box, using a screw or lug. There should be something in the box already. Driving a ground rod is a NEC code violation. This outlet is not a service nor is it a permanent structure. If you install a ground rod then you will be creating a ground loop. Example A fault or short will travel to the 30 amp outlet box see the ground rod, then travel through the ground to the electrical service and finally trip the breaker, maybe. Depends on the soil. Using a ground conductor it will travel on it and trip the breaker guaranteed.

Be safe out there.

Cite NEC reference(s) please.

Driving a rod does not violate anything. After all, we don't isolate everything from metal building structures (as in this case, mounted to a metal shed), we routinely bury metal conduit, we bond to buried water pipes, etc. There are usually many connections to earth in a system. Although there may be no reason for it, there is nothing wrong with grounding the box to the earth, including adding a ground rod, as long as there is an egc conductor, metal conduit, etc. that completes the path back to the service point. You can not rely on the earth as the sole fault current path, but it can be, and almost always is, part of it. Most of the current will flow through the metal path.

What is important is that the neutral is not bonded to the ground anywhere except the service entrance, other than the cases of a permanent structure with multiple receptacles and no egc, which is being covered in other threads.

Ben Miller

all from the 96 NEC

250-91 a b c

250-53

250-23 a last sentence "a grounding connection shall not be made to any grounded circuit on the load side of side of the service disconnect means."

250-24 does not apply as this is a outlet not a building

These discuss the grounding elecrode conductors at a service, and equipment grounding conductors. Nowhere does it say that the egc anywhere in the system can not be grounded to earth. As I pointed out previously, it will be in many cases.

The correct quote is"... grounded CIRCUIT CONDUCTOR..."

This refers to not grounding the neutral downstream of the service panel, which I believe everyone here agrees with. I stated that in my post as well. It says nothing about not connecting a grounding electrode to the enclosure, which is not a circuit conductor.

Ben Miller