sub-panels

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acrwc10 said:
For a detached structure I believe 230.79 also applies and has a direct relation to how many and what size conductors you need.
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230.79 has nothing to do with wire sizes.

On top of that Article 230 never applies to 'sub panels' only services. :smile:
 
iwire said:
OK, let me try.:)

I have a two floor house with a basement, the service panel is in the basement and I want to add a panel on the second floor, what code section requires that I run separate grounded and grounding conductors?
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How about 250.24(5)
 
steelersman said:
does 05 require you to drive new ground rod at new sub-panel for detatched building?
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Yes, if there are no other GE's available.

Roger
 
steelersman said:
does 05 require you to drive new ground rod at new sub-panel for detached building?
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Well it does not have to be a ground rod, it just has to be an electrode.

All feeders to separate building or structures require a grounding electrode and that requirement can be found in 225.32(A).
 
iwire said:
Well it does not have to be a ground rod, it just has to be an electrode.

All feeders to separate building or structures require a grounding electrode and that requirement can be found in 225.32(A).
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much appreciated info. Thanks.
 
detached building grounding/bonding

detached building grounding/bonding

Ok, if 2008 code requires (120/240) 4 wire to a detached building H-H-N-ECG and a ground rod and the subpanel has a main do you still have the neutral and ground bus separate and not any bonding screw at the neutral. Where is this in the code? How about 2005 code if we run 4 wire to the detached building how would we ground?:confused:
 
hotblueelectric said:
Ok, if 2008 code requires (120/240) 4 wire to a detached building H-H-N-ECG and a ground rod and the subpanel has a main do you still have the neutral and ground bus separate and not any bonding screw at the neutral. Where is this in the code? How about 2005 code if we run 4 wire to the detached building how would we ground?:confused:
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Under the 2008 NEC you must bring an equipment grounding conductor to a detached building. You must also install a grounidng electrode system if the building is being fed with a feeder. The grounding electrode system would be attached to the equipment grounding terminal in the disconnecting means for the structure. You would also isolate the neutral and the equipment grounds. Take a look at 250.32 for the grounding requirements for a separate structure.

The 2005 and earlier NEC editions had provisions for using the neutral for bonding purposes at a separate sturcture, but only if the structure didn't have any continious metallic paths bonded to the grounding system in each building or structure.

Chris
 
Try NEC 2008 250.142 B Load side equipment; grounded conductor ( neutral )shall NOT be used for NON current carrying metal parts
( grounded parts) therefore you will need the correct number of phase conductors, a grounded/neutral, and a grounding path.
 
I beleive that we wired a pool side open arbor (gazebo) in 2005 that had a hot tub, 2 ceiling fans, utility outlets and lights with a direct burial ser cable #6 with 2 hots, 1 neutral, and a ground. Installed a small 6 space panel with 1 50 amp cb for hot tub, 1 20 amp cb for outlets, and 1 15 amp cb for lights. All neutrals, grounds and grounding conductor on same bar with green bolt bonding the case. No ground rod. I assume this would be ok under 2005 code. Am I correct?
 
No, you would have had to install a grounding electrode at the structure. See 250.32 in it's entirety

Roger
 
hotblueelectric said:
Not back in the shop til Friday
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Ill post the 2008 section for you.:)
250.32 Buildings or Structures Supplied by a 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.
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.
(B) Grounded Systems. For a grounded system at the separate building or structure, an equipment grounding conductor as described in 250.118 shall be run with the supply conductors and be 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 or bonding of equipment, structures, or frames required to be grounded or bonded where all the requirements of (1), (2), and (3) are met:
(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).
Where the grounded conductor is used for grounding in accordance with the provision of this exception, 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
(C) Ungrounded Systems. The grounding electrode(s) shall be connected to the building or structure disconnecting means.
(D) Disconnecting Means Located in Separate Building or Structure on the Same Premises. Where one or more disconnecting means supply one or more additional buildings or structures under single management, and where these disconnecting means are located remote from those buildings or structures in accordance with the provisions of 225.32, Exception No. 1 and No. 2, 700.12(B)(6), 701.11(B)(5), or 702.11, all of the following conditions shall be met:
(1) The connection of the grounded conductor to the grounding electrode, to normally non?current-carrying metal parts of equipment, or to the equipment grounding conductor at a separate building or structure shall not be made.
(2) An equipment grounding conductor for grounding and bonding any normally non?current-carrying metal parts of equipment, interior metal piping systems, and building or structural metal frames is run with the circuit conductors to a separate building or structure and connected to existing grounding electrode(s) required in Part III of this article, or, where there are no existing electrodes, the grounding electrode(s) required in Part III of this article shall be installed where a separate building or structure is supplied by more than one branch circuit.
(3) The connection between the equipment grounding conductor and the grounding electrode at a separate building or structure shall be made in a junction box, panelboard, or similar enclosure located immediately inside or outside the separate building or structure.
(E) Grounding Electrode Conductor. The size of the grounding electrode conductor to the grounding electrode(s) shall not be smaller than given in 250.66, based on the largest ungrounded supply conductor. The installation shall comply with Part III of this article.
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Chris
 
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