I have contacted the electric company about putting an RV electrical post on some property. I need to dig a trench from the main pole to where I want to place the post. How close to the pole do I have to start, and how deep does it need to be. I was told 36" deep, but then I read it only has to be 18" if the wires are put in conduit. Then on a diagram it looks like it needs to be 24". Too many variables. I haven't contacted an electrician yet to do the hook up. This is all new to me. I Just need some answers that I can understand.

Don't know if your install is a feeder or a Service Entrance. Here, is some of the reasons for the discrepancies: New Page 1

36" is usually due to frost protection.

You have to deal with vehicular traffic.

I know there will be no traffic over this area except a lawn tractor or mower to cut the grass. The electric co. said they will feed the trench with enough line to get to where my post will be in the field. I guess I will ask the digger to go down 36" because of the possibility freezing.
Thanks for the diagrams.

Electrons don't freeze. Neither does wire. The 36" depth is mainly used for gas, water and sewer lines.

Imajor85,

You are confusing information from two different sources.

The Power Company is bound by Electrical Code of its own making.

The NEC is the electrical code that is used by customers of the power company for wiring up their installations.

For example the Power Company owns the wiring and power delivery up to the meter (or service entry point).

Typically, it is common for the POCO to require a 36" trench for their lateral (underground) services. It has nothing at all to do with frost.

The references to 12", 18" or 24" are references from the NEC requirements. These pertain to the running of feeders underground for residential use such as spas, pools or non attached buildings (garages)

If the Power Company told you to dig a trench 36" deep then that is what you should do. They will more than likely run a new Service Lateral to your mobile home connection point.

More than likely, they will connect to a transformer on the pole and run the service feed down the pole through a Sch. 80 PVC conduit that extend 36" below top grade and then to your connection point with another riser sch. 80 conduit to the service connection point.

This is the power company's call. No one else's.
Get the spec from them and follow it.

OK, So I have to dig a trench 3 feet deep from their pole to my post site where my RV electrical box will be. Thanks to all who gave info.