Going to quote this job soon. Being that this a travel trailer on wheels being fed from the main house 450' away I don't think this qualifies as a separate structure and no electrode system would be required, but I'm looking for opinions on this. He wants to be able to run his ac and fridge, etc in the travel trailer so vd is also a concern. It's a 120v 30 amp panel in the trailer. I was thinking a pedestal with the 30a receptacle and a few gfci's as well.

The pedestal you install meets the definition of 'separate structure' and needs a grounding electrode.

The trailer is listed as a unit to be supplied cord and plug without a ground rod at the trailer.

The size wire you choose is very much up to you and how much voltage drop you want to live with.

You mentioned the trailer is set up with a 30 amp plug, I will guess the load will not be more than 22 amps and that you could live with 5% voltage drop.

Using those figures you would need to run 3 AWG copper.

If you ran 10 awg for this distance and 22 amps of load you will have about 20% or 24 volts of loss.

To make a good decision on the wire size you must know what the connected load will really be.

I was planning on going with 2awg urd al. but wanted some opinions anyway. I wasn't sure about the pedestal being considered a separate structure because I know this has been debated here before and didn't remember the outcome. Driving a rod certainly isn't a big deal anyway. Thanks for verifying that.

With this sort of distance, would it be worth running the circuit at 240V and installing a transformer at the pedestal end?

Or is that going to make to project much too expensive?

Paul,
I agree...at least you'd have the 240v avail out there if you ever needed it. if the person ever traded in their trailor for one that needed 240v, you'd be covered. especially being that darn far away. would it be legal to cap one of the conductors for future use, and skip the transformer? I think so.
-Will

Yes, I'll probably recommend and quote for 240v. The #2 urd is relatively cheap and most homeowners out in these parts are looking for only one thing, low price. I'm guessing this guy is looking for advice and a quote and then he's going to do it himself anyway or call a handyman, happens alot out here. But, I guess at least I'll get to practice my estimating and sales skills.

Bob,
if you think that he's just using you, give'm only your price, not the brain work behind it.
-Will

Even though this could be considered a structure no ground rod is necessary. This is only a single circuit feeding a single receptacle. 250.32(A)Exc.

That's why I asked, I wasn't sure if this pedestal would be considered a structure and require an electrode. He also wants quad GFCI's installed on the pedestal as well, but from the same circuit of course. I guess I could try to get in touch with the inspector in that area and ask, he's just really hard to get a hold of. I will be as evasive as possible with this guy though, cause I just have a feeling he's a DIY'er and is looking for advice and wasting my time.

Two things about this.

1)This exception only applies to branch circuits. The 30 amp circuit is a feeder, there is a panel in the trailer.

2)BobH stated "I was thinking a pedestal with the 30a receptacle and a few GFCIs as well"

That sounds like more than one circuit.

You're right, sorry for the confusion as I haven't even seen the job site yet. Of course with Gfci's fed from a sub-panel the run would be a feeder. I'll see exactly what the customer wants first and then explain the options. If I install a sub for the gfci's, I'll definitely drive a rod, if I install only a pedestal with a rec. for the trailer to save money, being that there will probably be receptacles on the outside of trailer that are gfci protected I will verify the grounding requirements with the local inspector. I realize the trailer has it's own panel technically making the run a feeder if hard wired, but I wasn't certain being that it is cord connected. Depends on exactly what this customer wants besides the 30 a receptacle installed on the pedestal. I'll find out today.

Found out the run is over 600' and he does want separate gfci's near the pedestal. Figuring (with a safety factor) 25 amp draw with 600' feet I will have a vd of 4.8volts or roughly 4% with 2/0 aluminum urd. The supply house doesn't carry 1/0 urd. I'm quoting this with a pedestal mounted sub-panel, 4 wire feeder, and a grounding electrode. GfCI's fed from a 15 amp breaker offset nippled from the sub. 30 amp breaker for the TT receptacle. Sch. 80 pvc protecting the urd where it exits the earth. Any opinions on whether a pt 4x4 would be good enough for the support (sunk to frost line) or would you rather see a store bought pedestal.