250.92(A)

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ryan_618

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250.92 Services.
(A) Bonding of Services. The non?current-carrying metal parts of equipment indicated in 250.92(A)(1), (A)(2), and (A)(3) shall be effectively bonded together.
(1) The service raceways, cable trays, cablebus framework, auxiliary gutters, or service cable armor or sheath except as permitted in 250.84.
(2) All service enclosures containing service conductors, including meter fittings, boxes, or the like, interposed in the service raceway or armor.
DELETE the following: (3) Any metallic raceway or armor enclosing a grounding electrode conductor as specified in 250.64(B). Bonding shall apply at each end and to all intervening raceways, boxes, and enclosures between the service equipment and the grounding electrode.

Change to read:

250.92 Services.
(A) Bonding of Services. The non?current-carrying metal parts of equipment indicated in 250.92(A)(1), (A)(2), and (A)(3) shall be effectively bonded together.
(1) The service raceways, cable trays, cablebus framework, auxiliary gutters, or service cable armor or sheath except as permitted in 250.84.
(2) All service enclosures containing service conductors, including meter fittings, boxes, or the like, interposed in the service raceway or armor.

Substantiation:

Parenthetical 3 is an unnecessary redundancy. The requirement for bonding a metal enclosure for a grounding electrode is already spelled out clearly in 250.64(B). This requirement is not only for service equipment, which is the scope of 250.92, but also for separately derived systems, bonding jumpers for grounding electrodes. Sections 250.104(D) and 250.30(A)(3) and 250.30(A)(4) do not repeat the entire requirement of 250.64(C) like 250.92 does, because it is simply not necessary. 250.92 should address service equipment only, not service equipment and grounding electrode conductor enclosures. Also, article 100 defines service equipment as ?The necessary equipment, usually consisting of a circuit breaker(s) or switch(es) and fuse(s) and their accessories, connected to the load end of service conductors to a building or other structure, or an otherwise designated area, and intended to constitute the main control and cutoff of the supply?. An enclosure for a grounding electrode conductor does not fall into this definition.
 
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