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Report on Proposals May 2004 NFPA 70
Report on Proposals May 2004
NFPA 70
5-44 Log #2872 NEC-P05Meeting Action: Accept in Principle in Part
(250)
Final Action: Reject
TCC Action: Reject
It was the action of the Technical Correlating Committee that this Proposal be reported as "Reject" because less than two-thirds of
the members eligible to vote have voted in the affirmative.
Submitter: Paul Dobrowsky Holley, NY
Recommendation:
Revise Article 250 to read as follows:
[Text of Proposal 5-44 recommendation is shown on page __ ]
Substantiation:
The purpose of this proposal is to reorganize Article 250 based on a simple concept.
**Grounding. Grounded electrical systems are connected to earth (grounded) by a grounding electrode conductor. Ungrounded
electrical systems have their metal enclosures connected to earth (grounded) by a grounding electrode conductor.
**Bonding. Noncurrent carrying conductive materials enclosing electrical conductors or electrical equipment is connected together
(bonded) and to the supply source (bonded) ideally at the grounding point.
It is repeatedly stated that the earth is not an effective fault current path. The fault current path is provided by bonding. Connected
equipment is grounded through this bonding conductor, but only because of the grounding electrode conductor. If the grounding
electrode conductor was removed, the equipment would still be bonded but it would not be grounded. The existing term "grounding
conductor" could be used where equipment is "regrounded" at a point downstream of the grounding electrode conductor connection
(point of grounding).
Existing sections are reorganized in three parts: I General, II Grounding, III Bonding.
Existing Table 250.66 is in Part II as the grounding electrode conductor table. This same table is copied into Part III as 250.122(A) with
a note to use 12 1/2 percent for larger conductors to be used for supply side bonding conductors. Table 250.122 will be titled Load Side
Bonding Conductors and identified as 250.122(B).
The term earthing was included in parenthesis after the title to equate the term as used in other international and national standards. As
defined in one dictionary, the earth is "the third planet from the sun" using the term earth to include all of its elements (soil, rock, etc.) is
what we are trying to accomplish.
The term "ground" was deleted from some phrases such as "ground fault current path" because the current path is not through the earth
but through other conductive materials completing the circuit.
The term "equipment grounding conductor" was included in parenthesis after the new term "equipment bonding conductor". This
parenthetical term could be deleted in a future revision after a transition period.
Panel Meeting Action: Accept in Principle in Part
The panel accepts changing the term "equipment grounding conductor" to "equipment bonding conductor" as accomplished by the
action on Proposal 5-1 (Log #2453e).
The panel does not accept the reorganization as indicated in this proposal or the additional insertion of the term "earth" and its
derivatives.
Additionally change the following terms in the identified sections.
***INSERT TABLE L2872-HERE
(Table shown on page __)
Panel Statement:
Although this change is significant the panel concludes that it will improve the usability and consistent use of terms related to
grounding and bonding throughout the NEC. The panel understands that these adjustments need to be implemented in all other NEC
articles.
These terms and others such as bonding (bonded), bonding jumper, ground, grounded, grounded conductor, grounding, grounding
conductor, and equipment bonding jumper are interchanged and sometimes misused in many NEC sections and may need to be reviewed.
The panel requests that the Technical Correlating Committee review this action for implementation into all other NEC articles and
reflect this in the 2005 NEC Draft. This will provide an opportunity for determining any additional modifications that may be necessary.
Number Eligible to Vote: 16
Affirmative: 10 Negative: 6
Ballot Results:
Explanation of Negative:
BOKSINER: The clarification of the use of the words "grounded" and "grounding" in certain sections is needed. However, the changes
proposed in this panel action does nothing to improve clarity. The majority of the changes are simple replacements of "grounded" with
"bonded". This does not improve clarity because the definition of the word "bonded" is very generic. The definition in Article 100 is:
"Bonding (Bonded). The permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity
and the capacity to conduct safely any current likely to be imposed."
Thus, to change "grounded" which implies a connection to particular location, with "bonded" is meaningless. As an example, consider
250.114. This section presently states:
"...exposed non-current-carrying metal parts of cord- and plug-connected equipment likely to become energized shall be grounded."
Under the present proposal this phrase would become
"...exposed non-current-carrying metal parts of cord- and plug-connected equipment likely to become energized shall be bonded."
"bonded" to what? Would connecting cases of two computers in a rack satisfy this requirement? It would according to the definition of
"bonding."
The existing requirement should be made more clear and specific, instead the rewording in the proposed panel action makes the
requirement less specific. The appropriate change would be to revise 250.114 using a language similar to the following:
"...exposed non-current-carrying metal parts of cord- and plug-connected equipment likely to become energized shall be connected to
an equipment grounding conductor run with the circuit conductors."
This discussion applies to the majority of changes accepted in this proposal. This proposal will reduce the clarity of the NEC and
should be rejected.
BRENDER: See my Explanation of Negative Vote on Proposal 5-1.
BRETT: See my Explanation of Negative Vote on Proposals 5-1 and 5-41.
HAMMEL: See my Explanationof Negative Vote on Proposal 5-1.
RAPPAPORT: I agree with the panel to reject the reorganization and I reject changing the term "equipment grounding conductor" to
"equipment bonding conductor". See my Explanation of Negative Vote on Proposal 5-1.
STEINMAN: NEMA disagrees with the panel action. The proposal has fostered significant debate in the Code process. After considering
all debate, it is clear that the issue is one of education and not terminology. Changing the term "grounding" to "bonding" in no way
changes the need for qualified persons and continuing education. The present terminology is well understood by those who understand
the purposes of grounding and bonding. The panel members and public need to consider the magnitude of the change compared to the
benefit. The change will create a nightmare of revisions and changes in terminology across the electrical system. The benefit is
practically nonexistent.
Comment on Affirmative:
DOBROWSKY: Changing the term "equipment grounding conductor" (EGC) to "equipment bonding conductor" (EBC) will improve
the NEC's usability and reduce misinterpretations. Presently the terms "grounding", "bonding", and their derivatives are frequently
used interchangeably - sometimes when describing very different requirements. In most cases, the "EBC" will still have a connection to
the system grounding point" but the grounding electrode conductor actually accomplishes the grounding.
Because of the excellent work done by CMP 1 by adding a fine print note, indicating that in previous NEC editions "EGC" was used to
describe "EBC," product standards and manufacturer's literature can be updated during their normal revision processes. This will
minimize the financial impact to the electrical industry yet allow an improvement that uses the terms consistently. Implementing the
change at the ROP stage of the process will highlight any sections that need to be adjusted before the 2005 NEC revision is completed.
Other definitions contained in Article 100 also need modification to improve the understanding of grounding and bonding concepts.
As the submitter, I was fortunate to be included in discussions with many individuals concerned with the proposed changes in terms.
The amount of confusion is clearly apparent.
JOHNSTON: The inclusion of the term "and bonding" in the title of the article is consistent with th