fmtjfw
Senior Member
- Location
- Fairmont, WV, USA
Section/Paragraph: 210.5(C)(2)
Revised Text
210.5 Identification for Branch Circuits.
....
(C) Identification of Ungrounded Conductors.
....
(2) Branch Circuits Supplied From Direct-Current Systems.
Where a branch circuit is supplied from a dc system operating at more than 50 volts, each ungrounded conductor of 4 AWG or larger shall be identified by polarity at all termination, connection, and splice points by marking tape, tagging, or other approved means; each ungrounded conductor of 6 AWG or smaller shall be identified by polarity at all termination, connection, and splice points in compliance with 210.5(C)(2)(a) and (b). The identification methods utilized for conductors originating within each branch-circuit panelboard or similar branch-circuit distribution equipment shall be documented in a manner that is readily available or shall be permanently posted at each branch-circuit panelboard or similar branch-circuit distribution equipment.
(a) Positive Polarity, Sizes 6 AWG or Smaller. Where the positive polarity of a dc system does not serve as the connection point for the grounded conductor, each Each positive ungrounded conductor shall be identified by one of the following means:
(1) A continuous red outer finish
(2) A continuous red stripe durably marked along the conductor?s entire length on insulation of a color other than green, white, gray, or black
(3) Imprinted plus signs (+) or the word POSITIVE or POS durably marked on insulation of a color other than green, white, gray, or black, and repeated at intervals not exceeding 610 mm (24 in.) in accordance with 310.120(B)
(b) Negative Polarity, Sizes 6 AWG or Smaller. Where the negative polarity of a dc system does not serve as the connection point for the grounded conductor, each Each negative ungrounded conductor shall be identified by one of the following means:
(1) A continuous black outer finish
(2) A continuous black stripe durably marked along the conductor?s entire length on insulation of a color other than green, white, gray, or red
(3) Imprinted minus signs (?) or the word NEGATIVE or NEG durably marked on insulation of a color other than green, white, gray, or red, and repeated at intervals not exceeding 610 mm (24 in.) in accordance with 310.120(B)
Substantiation:
"Where the {positive|negative} polarity of a dc system does not serve as the connection point for the grounded conductor" is redundant and unnecessary, the following "each {positive|negative} ungrounded conductor..." suffices to eliminate grounded conductors.
The sections 210.5(C)(2) and 215.12(C)(2) are nearly identical. They differ by the use of "branch circuit" and "feeder". Internal references differ, but have the same meaning. They also have to begin to diverge by the addition of "point" in 210.5(C)(2) in connection with grounded conductors. There is a dictum from computer science that states "if you put the same information in two places, eventually it will change in one and not the other, so don't do it".
I see no particular need to repeat nearly a whole column with the same meaning in the feeder article when it already appears in the branch-circuit article. The practice of referring to other sections for conductor colors is supported by that method being used in 210.5(A) and (B) and 215.12(A) and (B).
Approval of this change should be co-ordinated with the approval of my change to 215.12(C)(2).
insert delete
Revised Text
210.5 Identification for Branch Circuits.
....
(C) Identification of Ungrounded Conductors.
....
(2) Branch Circuits Supplied From Direct-Current Systems.
Where a branch circuit is supplied from a dc system operating at more than 50 volts, each ungrounded conductor of 4 AWG or larger shall be identified by polarity at all termination, connection, and splice points by marking tape, tagging, or other approved means; each ungrounded conductor of 6 AWG or smaller shall be identified by polarity at all termination, connection, and splice points in compliance with 210.5(C)(2)(a) and (b). The identification methods utilized for conductors originating within each branch-circuit panelboard or similar branch-circuit distribution equipment shall be documented in a manner that is readily available or shall be permanently posted at each branch-circuit panelboard or similar branch-circuit distribution equipment.
(a) Positive Polarity, Sizes 6 AWG or Smaller. Where the positive polarity of a dc system does not serve as the connection point for the grounded conductor, each Each positive ungrounded conductor shall be identified by one of the following means:
(1) A continuous red outer finish
(2) A continuous red stripe durably marked along the conductor?s entire length on insulation of a color other than green, white, gray, or black
(3) Imprinted plus signs (+) or the word POSITIVE or POS durably marked on insulation of a color other than green, white, gray, or black, and repeated at intervals not exceeding 610 mm (24 in.) in accordance with 310.120(B)
(b) Negative Polarity, Sizes 6 AWG or Smaller. Where the negative polarity of a dc system does not serve as the connection point for the grounded conductor, each Each negative ungrounded conductor shall be identified by one of the following means:
(1) A continuous black outer finish
(2) A continuous black stripe durably marked along the conductor?s entire length on insulation of a color other than green, white, gray, or red
(3) Imprinted minus signs (?) or the word NEGATIVE or NEG durably marked on insulation of a color other than green, white, gray, or red, and repeated at intervals not exceeding 610 mm (24 in.) in accordance with 310.120(B)
Substantiation:
"Where the {positive|negative} polarity of a dc system does not serve as the connection point for the grounded conductor" is redundant and unnecessary, the following "each {positive|negative} ungrounded conductor..." suffices to eliminate grounded conductors.
The sections 210.5(C)(2) and 215.12(C)(2) are nearly identical. They differ by the use of "branch circuit" and "feeder". Internal references differ, but have the same meaning. They also have to begin to diverge by the addition of "point" in 210.5(C)(2) in connection with grounded conductors. There is a dictum from computer science that states "if you put the same information in two places, eventually it will change in one and not the other, so don't do it".
I see no particular need to repeat nearly a whole column with the same meaning in the feeder article when it already appears in the branch-circuit article. The practice of referring to other sections for conductor colors is supported by that method being used in 210.5(A) and (B) and 215.12(A) and (B).
Approval of this change should be co-ordinated with the approval of my change to 215.12(C)(2).
insert delete