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#54358 07/27/05 11:51 AM
Joined: Oct 2004
Posts: 135
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BobH Offline OP
Member
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.

Joined: Jan 2003
Posts: 4,391
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Moderator
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.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Joined: Oct 2004
Posts: 135
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BobH Offline OP
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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.

Joined: Aug 2001
Posts: 7,520
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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?

Joined: Aug 2004
Posts: 54
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Member
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

Joined: Oct 2004
Posts: 135
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BobH Offline OP
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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.

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

Joined: Aug 2003
Posts: 173
S
Member
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.


Speedy Petey

"Anyone who has never made a mistake has never tried anything new." -Albert Einstein
Joined: Oct 2004
Posts: 135
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BobH Offline OP
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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.

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Quote
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.

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. [Linked Image]


Bob Badger
Construction & Maintenance Electrician
Massachusetts
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