250.50 Structure/Building Served

[quantum]

NEC - 250.50 Grounding ElectrodeSystem.All grounding electrodes as described in250.52(A)(1) through (A)(7) that arepresent at each building or structure servedshall be bonded together to form thegrounding electrode system. Where none ofthese grounding electrodes exist, one ormore of the grounding electrodes specifiedin 250.52(A)(4) through (A)(8) shall beinstalled and used.

It says, each building or structure served, does this mean only building or structures that have service equipment? What if I have a skid on a rebar/concrete pad with a panel being sourced with a feeder? What if I have a skid with a rebar/concrete pad being supplied by a branch circuit? Do those rebars need to be grounded if they are of sufficient length? What does served exactly mean in this case?

 

[jumper]

250.112(K) requires skids to be connected to an EGC, but I am not totally convinced that a GES, 250.52 lists types of GEs, required by 250.32 is required. A skid may or may not be a structure, IDK.

Structure.
That which is built or constructed

My opinion is that structures are not usually portable per se.

 

[ActionDave]

What if I have a skid with a rebar/concrete pad being supplied by a branch circuit? Do those rebars need to be grounded if they are of sufficient length? What does served exactly mean in this case?

250.52(3) says 'foundation or footing'. I always understood that to mean below grade. I don't think a concrete skid counts as a foundation or footing any more than a side walk.

 

[quantum]

"All grounding electrodes as described in 250.52(A)(1) through (A)(7) that are present at each building or structure served shall be bonded together to form the grounding electrode system"

I'm more concerned with the use or definition of the word served. All grounding electrodes have to be bonded together if they are present at each building or structure "served".

When is a building or structure considered to be "served" ?

 

[ActionDave]

When is a building or structure considered to be "served" ?[/COLOR]

When it has power run to it.

You only need a GES if you have more than one circuit.

 

[GoldDigger]

"All grounding electrodes as described in 250.52(A)(1) through (A)(7) that are present at each building or structure served shall be bonded together to form the grounding electrode system"

I'm more concerned with the use or definition of the word served. All grounding electrodes have to be bonded together if they are present at each building or structure "served".

When is a building or structure considered to be "served" ?

IMHO when the electrical "service" to the building has one or more outlets in or on that building.

A disconnect on the outside of a structurewith a feeder coming in from one building and one going out to another building would not "serve" the building it is mounted on.
Add a single receptacle outlet and you now have "service".
This is not just a wild hypothetical: consider a post on which a disconnect is mounted near the building it feeds power to. That post is arguably a structure, but not one that is served by the wiring.

 

[iwire]

IMHO when the electrical "service" to the building has one or more outlets in or on that building.

A disconnect on the outside of a structurewith a feeder coming in from one building and one going out to another building would not "serve" the building it is mounted on.
Add a single receptacle outlet and you now have "service".
This is not just a wild hypothetical: consider a post on which a disconnect is mounted near the building it feeds power to. That post is arguably a structure, but not one that is served by the wiring.

I disagree with that and feel it will be an AHJ call

 

[jumper]

I disagree with that and feel it will be an AHJ call

225.11 tends to agree with you

225.11 Feeder and Branch-Circuit Conductors Enter-
ing, Exiting, or Attached to Buildings or Structures.
Feeder and branch-circuit conductors entering or exiting
buildings or structures shall be in installed in accordance
with the requirements of 230.52. Overhead branch circuits
and feeders attached to buildings or structures shall be in-
stalled in accordance with the requirements of 230.54

 

[kwired]

When it has power run to it.

You only need a GES if you have more than one circuit.

+1

And in general you are only allowed one service, one feeder or one branch circuit to a building or structure. Service and feeder supplied buildings need a GES, branch circuit supplied structure, GES is optional.