Article 250.50

[steve grayson]

I am new to this forum, so I am sure this topic has been kicked around many times (I have just missed the fun). 'If available' seems to indicate that there is an option to bonding all six items. If the construction is new and the Architect or building owner indicates they do not want the building steel bonded or a grounding electrode in their footing, is it available? If the electrician can buy the rod and pipe electrode from the supply house, is it available? What about the plate electrodes? Should the supply houses start stocking plate electrodes? The last sentence indicates to me that in special circumstances a rod or pipe electrode could be the only grounding electrode connected to a service.

 

[charlie b]

Re: Article 250.50

That?s a new twist on the use (or misuse?) of language, in the creation of new interpretations. Your second question is the easiest to answer. The item must be on the premises. That doesn?t mean in someone?s truck, it means deliberately placed in dirt, with the intent that it be used as part of the grounding electrode system. The answer to your first question is that the owner?s and architect?s desires mean nothing. If the structural designer has made it physically impossible for a wire to be attached to the building steel, then it is not available. Otherwise it is. As you your final point, I?m sure there are at least two buildings (there might be more)

 

[tom baker]

Re: Article 250.50

A ufer ground is not required to be used, (250.52 (A)(3)Even if on the premise. This was clarifed by NFPA Formal Interpertation 78-4, and is shown the NEC handbook

 

[eprice]

Re: Article 250.50

Originally posted by tom baker:
A ufer ground is not required to be used, (250.52 (A)(3)Even if on the premise. This was clarifed by NFPA Formal Interpertation 78-4, and is shown the NEC handbook

Tom,

I want to be sure I understand what you are saying here. I think you mean that just because there is a 20' or more length of rebar in the footing, if it hasn't been made available to the electrician by bringing a connection point out of the foundation, the electrician is not required to use it. I believe that if it has been made available, then 250.50 requires that it be used.

 

[websparky]

Re: Article 250.50

2002 NEC Handbook
Formal Interpretation 78-4
Reference: Article 250.50
Question: Is it the intent of 250.50 that reinforcing steel, if used in a building footing, must be made available for grounding?
Answer: No.
Issue Edition: 1978
Reference: 250-81
Issue Date: March 1980

250.50 Grounding Electrode System.
If available on the premises at each building or structure served, each item in 250.52(A)(1) through (A)(6) shall be bonded together to form the grounding electrode system. Where none of these electrodes are available, one or more of the electrodes specified in 250.52(A)(4) through (A)(7) shall be installed and used.

250.52 (A)
(4) Ground Ring.
(5) Rod and Pipe Electrodes.
(6) Plate Electrodes.
(7) Other Local Metal Underground Systems or Structures. Other local metal underground systems or structures such as piping systems and underground tanks.