Subpanel wired as main panel.

[jlybolt]

Home is out in the country. Overhead power lines go to electrical post and down to panel with 200 amp main breaker with ground rod. The service then exits the panel and goes under ground about 50 feet to another panel at the rear exterior of the home which also has a 200 main breaker and also wired as a main panel with no isolating grounds/ neutrals. Am I missing something here or isnt the panel at the house suppose to be wired as a subpanel? Grounds and grounded conductor seperated?
First image is panel at home, 2nd image panel at utility post about 50 feet away.

[Speedy Petey]

This is typical/standard. As long as there are no metallic paths between structures, which is highly doubtful considering one "structure" is a pedestal, you can run a 3-wire feeder between panels. The remote panel gets treated the same as a "main" panel.
This is what was done in this photos.
The pedestal panel is a feed-through panel if you notice in the pic. That is what the lugs on the bottom of the buss are for.

[jlybolt]

Sorry, im little lost on this one. I always thought no matter what panels that are past the main panel have to be wired as subpanels. Can you explain feed through panel to me and why you wouldnt have to seperate the neutrals/grounds at the house panel.

[jlybolt]

there is four wires exiting the panel going to the panel at the house.

[Paul W. Abernathy]

(2) Grounded Conductor.

Where (1) an equipment
grounding conductor is not run with the supply to the building
or structure, (2) there are no continuous metallic paths
bonded to the grounding system in each building or structure
involved, and (3) ground-fault protection of equipment

has not been installed on the supply side of the feeder(s),
the grounded conductor run with the supply to the building
or structure shall be connected to the building or structure
disconnecting means and to the grounding electrode(s) and
shall be used for grounding or bonding of equipment, structures,
or frames required to be grounded or bonded. The
size of the grounded conductor shall not be smaller than the
larger of either of the following:
(1) That required by 220.61
(2) That required by 250.122

Basically it is an exception that allows this in detached garages or structure...do not let it confuse you on standard 4 wire setups to any " Remote Distribution Panel" you would see in a standard dwelling...that would need to be a 4 wire setup ( or 3 wires with metal conduit in Chicago.lol ) so basically.........the running of 3 conductors to a detached building is an exception to the allowance but the conditions of the statements above govern IF this can take place......hope that explains it.

[Greg Fretwell]

In 2008 that will all go away and you will be using 4 wire feeders and separated ground/neutral on all sub panels.

[Paul W. Abernathy]

FINALLY........I am all for that as the exception was always a source of controvery to many.....greg has that made it into the final revision yet as I have held off going over the 2008 since I wont be starting to teach it nationwide until October 2007.

[Paul W. Abernathy]

Yeppers......greg is totally perfect as usual...

250.32 Buildings or Structures Supplied by Feeder(s) or
Branch Circuit(s).
(A) Grounding Electrode.

Building(s) or structure(s) supplied
by feeder(s) or branch circuit(s) shall have a grounding
electrode or grounding electrode system installed in
accordance with Part III of Article 250. The grounding
electrode conductor(s) shall be connected in accordance
with 250.32(B) or (C). Where there is no existing grounding
electrode, the grounding electrode(s) required in 250.50
shall be installed. [ROP 5–120]

Exception: A grounding electrode shall not be required
where only a single branch circuit, including a multiwire
branch circuit, supplies the building or structure and the
branch circuit includes an equipment grounding conductor
for grounding the normally non–current-carrying metal
parts of equipment.

[ROP 5–118, 5–76]
(B) Grounded Systems. For a grounded system at the
separate building or structure, the connection to the grounding
electrode, the grounding and bonding of equipment,
structures, or frames required to be grounded and bonded
shall comply with 250.32(B)(1). [ROP 5–77, 5–119,
5–121a]
(1) Equipment Grounding Conductor. An equipment
grounding conductor as described in 250.118 shall be run
with the supply conductors and connected to the building or
structure disconnecting means and to the grounding electrode(
s). The equipment grounding conductor shall be used
for grounding or bonding of equipment, structures, or
frames required to be grounded or bonded. The equipment
grounding conductor shall be sized in accordance with
250.122. Any installed grounded conductor shall not be
connected to the equipment grounding conductor or to the
grounding electrode(s).

Exception: For existing premises wiring systems only, the
grounded conductor run with the supply to the building or
structure shall be permitted to be connected to the building
or structure disconnecting means and to the grounding
electrode(s) and shall be used for grounding and bonding
of equipment, structures, or frames required to be grounded
and bonded where all the following requirements of (1), (2),
and (3) are met:

[ROP 5–76, 5–119]

(1) An equipment grounding conductor is not run with the
supply to the building or structure.
(2) There are no continuous metallic paths bonded to the
grounding system in each building or structure involved.
(3) Ground-fault protection of equipment has not been installed
on the supply side of the feeder(s).

[ROP 5–119,
5–76]

[jlybolt]

OK if I am understanding this correctly, four wires run to the panel at the exterior of the home would require isolating neutrals and grounds.

If that is the case I have four wires exiting the panel at the pedestal.

Sorry for not understanding. The light bu lb hasnt come on yet.

[Paul W. Abernathy]

Ahhh...the use of the word exterior make is more confusing to you James....4 wire setups need to run to ANY " remote distribution panel" located in or on the dwelling in question.....the exception to the rule is for lets say a detached building or structure and as long as the conditions apply 3 conductors to that building is allowed....does not make it safe...just accepted.

But if you are talking about a " remote distribution panel " within the same structure must have the 4 wire setup and proper seperation to be complaint.

Hope that explains it better

[jlybolt]

Got it, I am little hard headed sometimes. Well most of the time. Thanks everyone for the help with this one. Its the first time I ever have seen this set up.

[jlybolt]

Exception: For existing premises wiring systems only, the

grounded conductor run with the supply to the building or
structure shall be permitted to be connected to the building
or structure disconnecting means and to the grounding
electrode(s) and shall be used for grounding and bonding
of equipment, structures, or frames required to be grounded
and bonded where all the following requirements of (1), (2),
and (3) are met:
[ROP 5–76, 5–119]

(1) An equipment grounding conductor is not run with the

supply to the building or structure.
(2) There are no continuous metallic paths bonded to the
grounding system in each building or structure involved.
(3) Ground-fault protection of equipment has not been installed
on the supply side of the feeder(s).

[ROP 5–119,
5–76]
__________________________________________________-
One more question, (1) says an equipment grounding conductor is not run with the supply to the building or structure. Doenst that mean since I have four wires leaving the panel at the pedestal that the remote panel should be wired as a subpanel?

[Paul W. Abernathy]

(1) simply is saying that.......if you are using this allowable existing exception that no equipment grounding conductor ( which is the 4th wire in a 4 wire set-up ) has not actually been run...because if it WAS...then you would not be able to use this exception...meaning you would need to use the EGC that is present........so it is simply for clarrification.

[Speedy Petey]

Originally Posted by jlybolt

there is four wires exiting the panel going to the panel at the house.

Sorry then. From what I can see in the pics it looks like only three. In that case it is not cool as you all have been discussing.

[Paul W. Abernathy]

Yikes....I think we need some clarity here......this gets hard to follow and we need to make sure they are clear on this...

1.) I am with Peter in that I simply took the picture as (3) conductors going from the main panel to the panel at the house which becomes a " Remote Distribution Panel "...which is acceptacle under current provisions as long as the provisions are met.......

Now.....as Peter stated and I had to go back and READ what james had posted as I was QUICK to post......that indeed (4) conductors are present to the panel at the house.......honestly I only see (3) because I will HOPE that solid bare conductor on the terminal is going to a rod of sorts at the exterior ( pole ) set main panel...as it should be.

Ok...at the panel on the pole ( for clarrification ) the grounded and grounding conductors share the termination buss as they should.....but if a 4th conductor is run to the dwelling as James states...then it MUST be a seperation at the dwelling panel...no exceptions on that.

Again as always ( for education sake ) I want to bring it all back together in the end in case someone jumps in a reads only the ending of the conversation.....which BTW is not a good thing to do...

Now if my vision is right ...if you are saying that BARE conductor runs all the way to the "Remote Distribution Panel " and is is larger than a # 8 CU...it must be stranded if in conduit.......( lets not get into conduit as the 4th conductor right now...just not worth it in this example )