Multiple Buildings Grounding and Bonding...

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emahler

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Here is the setup...a farm with 3 buildings...the Poco service comes into building one...here it feeds building 1 and has a disconnect for building 2...building 2 in turn feeds a panel in building 3.

Building 1 is a storage building, existing for unknown amount of time. The water is from a well.

Building 2 is a new storage barn/workshop....no rebar and no concrete floor.

Building 3 is an indoor riding arena...it's also new and has a sand floor...

How would you ground and bond these buildings...forget wiring sizing...just the physical act...
 
I usually install a grounding conductor to separate buildings. When I do this the grounded conductor is not bonded the the service enclosure for that building. To make it easy in my brain I think of it like a sub panel, only that there will be an electrode established at the out buildings. and the GEC connected to the equipment grounding bar and not the grounded conductor bar. No bond jumper from the grounded conductor to the enclosure.
 
frizbeedog said:
I usually install a grounding conductor to separate buildings. When I do this the grounded conductor is not bonded the the service enclosure for that building. To make it easy in my brain I think of it like a sub panel, only that there will be an electrode established at the out buildings. and the GEC connected to the equipment grounding bar and not the grounded conductor bar. No bond jumper from the grounded conductor to the enclosure.
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that way works...
 
emahler said:
Plan PVC with Copper...

would you run an EGC?
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Yes, but your OP made it sound like Bldgs 1 and 2 have existing feeders.


(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.
 
chris kennedy said:
(D) Disconnecting Means Located in Separate Building or Structure on the Same Premises. .
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Would (D) be applicable for this? Just tyring to picture that application. I havn't experieced that on farms and such.

"...and where these disconnecting means are located remote from those buildings or structures..."
 
emahler said:
How would you ground and bond these buildings...forget wiring sizing...just the physical act...
Click to expand...

1) Grounding & Bonding

Each separate building or structure supplied with a feeder needs a grounding electrode system. 250.32)(A).

The rules are exactly the same as for a service. Use the electrodes that are already present and / or add ones.

This GES must be tied into the grounding bus at the sub panel

2)EGC with feeder or not.

Unless you are under the 2008 NEC you may have a choice if you run an EGC or not. 250.32(B)(1) and (2)

If there are no other metallic paths between the buildings that are bonded at each building then you can leave the EGC out.

If you leave the EGC out you treat the sub panel exactly like a service, you must bond the neutral to panel enclosure and GES.
 
frizbeedog said:
Would (D) be applicable for this? Just tyring to picture that application. I havn't experieced that on farms and such.

"...and where these disconnecting means are located remote from those buildings or structures..."
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Am I misunderstanding this?

emahler said:
Here is the setup...a farm with 3 buildings...the Poco service comes into building one...here it feeds building 1 and has a disconnect for building 2...building 2 in turn feeds a panel in building 3.
Click to expand...
 
iwire said:
If there are no other metallic paths between the buildings that are bonded at each building then you can leave the EGC out..
Click to expand...

Question is...How do we verify that for existing installations?
 
iwire said:
1) Grounding & Bonding

Each separate building or structure supplied with a feeder needs a grounding electrode system. 250.32)(A).

The rules are exactly the same as for a service. Use the electrodes that are already present and / or add ones.

This GES must be tied into the grounding bus at the sub panel

2)EGC with feeder or not.

Unless you are under the 2008 NEC you may have a choice if you run an EGC or not. 250.32(B)(1) and (2)

If there are no other metallic paths between the buildings that are bonded at each building then you can leave the EGC out.

If you leave the EGC out you treat the sub panel exactly like a service, you must bond the neutral to panel enclosure and GES.
Click to expand...


will this be a change in 2008? we are still under 2005bn
 
frizbeedog said:
Question is...How do we verify that for existing installations?
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See where the bonding conductors lead to in the existing building?

It's a moot point, once the 2008 is adopted that option disappears.
 
ryan_618 said:
I know how much of a fan you are of this change, so I'll just say "you're welcome". ;)
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this was your doing? i'll give my customers your number when they complain about the cost:D
 
ryan_618 said:
I know how much of a fan you are of this change, so I'll just say "you're welcome". ;)
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I went through the five stages.


1-Denial-"this can't be happening to me"

2-Anger-"why me?"

3-Bargaining

4-Depression

5-Acceptance


I am over it. :grin:
 
emahler said:
let's just say, ryan is posting from his yacht in the caribbean right now...
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Look at his car, ;)

4822_8110565643.jpg
 
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