service to a trailer

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mh183

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came to a job there is a disconnect about 40' from the pole the power co. requested the at that location for easy location to read it. then the trench goes down a hill ant turns to the trailer approx 200' at that point goers into a 12" by 12" pvc box and splits to two disconnects ground rode is brought in to the 12*12.
my question is by putting the disconnect at the meeter isn't every thing down line 4 wire and sub panel . with possible exception that the power co. requested the disconnect for service to the meeter ?
 
mh183 said:
came to a job there is a disconnect about 40' from the pole the power co. requested the at that location for easy location to read it. then the trench goes down a hill ant turns to the trailer approx 200' at that point goers into a 12" by 12" pvc box and splits to two disconnects ground rode is brought in to the 12*12.
my question is by putting the disconnect at the meeter isn't every thing down line 4 wire and sub panel . with possible exception that the power co. requested the disconnect for service to the meeter ?

Yes,I would say 4 wires from the disco to the trailer.
 
Look at section 550.4 general requirements and 550.10 (I) (1) 4 insulated, color-coded feeder conductors. Also 550.11 (A).
 
SEO said:
Look at section 550.4 general requirements and 550.10 (I) (1) 4 insulated, color-coded feeder conductors. Also 550.11 (A).

Where would this requirement start?
Would it be at the disconnect at the meter or the service disconnect at the junction box?

I agree with Iwire.
 
SEO said:
Are you sure for a trailer?:smile:

Of course I am. ;)

Actually I am not sure that is why I said 'could' not would.

I guess it makes sense to assume this trailer is covered by 550 but we don't really know that. :smile:
 
iwire said:
Of course I am. ;)

Actually I am not sure that is why I said 'could' not would.

I guess it makes sense to assume this trailer is covered by 550 but we don't really know that. :smile:
The title of the thread is Service To a Trailer that puts me into Article 550. Section 550.4 lists types of trailers. The 4 insulated wires start where the feeder receives its supply, section 250.32 is building or structures a trailer is not a building or structure.:smile:
 
SEO said:
The title of the thread is Service To a Trailer that puts me into Article 550.

Your assuming it is that kind of trailer, it likely is but we don't know that.

It could be a job trailer, it could be the trailer from a semi truck being used as storage building... my point is we just don't know.

I have helped install a 4000 amp 480 volt service into a Semi Trailer and now it is dragged along to large construction projects as a temporary power distribution unit. :)
 
SEO said:
a trailer is not a building or structure.:smile:

Yea I understand what you are saying here. When we bought this farm a plane flew over scattering a bunch of seeds and wham-O a bunch of single wide trailers just grew up out of nowhere.

I wouldn?t think that the requirements for the feeders to the mobile home would kick in until after the split to two disconnects at the junction box.

From the disconnect located at the meter to the two disconnect located at the junction box couldn?t very well be the feeder to a trailer.
 
SEO said:
a trailer is not a building or structure.:smile:

I overlooked that part, I have to disagree. There is no doubt that a trailer is a structure, it may even be a building.

But that is not a problem because of 90.3 .... 'Chapters 1-4 apply unless modified by chapters 5, 6 and 7.' (My words)

225.32 is in Chapter 2 but can be amended by items in 550.

Like Mike I am curious to where it starts but with the removal of 225.32(B)(2) for 2008 it becomes a moot point.
 
iwire said:
I overlooked that part, I have to disagree. There is no doubt that a trailer is a structure, it may even be a building.

But that is not a problem because of 90.3 .... 'Chapters 1-4 apply unless modified by chapters 5, 6 and 7.' (My words)

225.32 is in Chapter 2 but can be amended by items in 550.

Like Mike I am curious to where it starts but with the removal of 225.32(B)(2) for 2008 it becomes a moot point.
The definition of a structure is that which is built or constructed (NEC definition) so I agree it could be a structure. With information listed on first thread I used section 550 it could be art 551 or 552 . I used 550 thinking of a contractor's on-site office wheeled on site for construction and removed after completion of project. Section 551.40 (A) requires a 4-wire system and 552.40 (A) does as well. I guess it's another question for the local AHJ to classify what section to use.:smile:
 
sorry to post and run service calls all day. this is a construction style trailer on weals and a frame which is going to be a long term or permanent office. it was supposed to be a building but funding fell through so now it is a donated trailer on a frame on weals
 
mh183 said:
came to a job there is a disconnect about 40' from the pole the power co. requested the at that location for easy location to read it. then the trench goes down a hill ant turns to the trailer approx 200' at that point goers into a 12" by 12" pvc box and splits to two disconnects ground rode is brought in to the 12*12.
my question is by putting the disconnect at the meeter isn't every thing down line 4 wire and sub panel . with possible exception that the power co. requested the disconnect for service to the meeter ?

mh183, The way I read 550.4(B) and 550.4(C) the 3 wire to the two disconnects

are service conductors, the disconnects are fusible, correct ? Follow 550.32

for connecting from the disco to the trailer. Grounding at disco 250.32
 
Interesting

Interesting

I had a similar question about a 'temporary mri hospital' trailer, that is now a 'permanant' . Well they had a 3 wire going to it, 480 volts. 3 hots 1 ground. I know they had probably a transformer for the 120 208 loads, and these wires feeding this trailer was a 'FEEDER' and NOT a service. The original manufacturers instructions had originally had a 'neutral' for this feeder basically 5 wires, 3 hots, 1 neutral 1 ground, but the engineer had talked with them (manufacturer) and they decided it was ok to not have to run the neutral for the MRI.

I dont think this is a 'code' compliant 250.32 install in my opinion, but aparrently it works just fine. Maybe there is a 'delta' transformer there, but i was always taught/believe that any time you had 120 line to neutral loads on a 'seperate' structure' or trailer (which this is now) then you HAVE to seperate the grounds and neutrals for the FEEDERS even if there is a transformer in this structure/building/trailer. I know they would would be 'bonding' the neutral and ground at this transformer or first panel, but it just doesnt seem to comply with 250.32
Am I right?? Even if it doesnt fall under 550, 551, 552, .
 
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