51 lines
1.5 KiB
Markdown
51 lines
1.5 KiB
Markdown
---
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id:
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aliases: []
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tags:
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- destiny/fleeting
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- topic/electrical
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- type/encyclopedia
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---
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# Feeder Sizing
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> [!cite] 250.122 Size of Equipment Grounding Conductors
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> **(A) General.** Copper, aluminum, or copper-clad aluminum
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> equipment grounding conductors of the wire type
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> shall not be smaller than shown in Table 250.122,
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> but in no case shall they be required to be larger
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> than the circuit conductors supplying the equipment...
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Apparently in the 2026 NEC First Draft Meetings,
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Code Making Panel 5 clarified that the equipment grounding conductor (EGC)
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never needs to be larger than the largest ungrounded conductor in any raceway
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when installed in parallel.
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I can not find a source to verify this.
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Statements from other reputable sources including Mike Holt
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are in contradiction to this idea.
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***
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Given a minimum ampacity, find all valid configurations.
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> [!cite] 310.10(H) Conductors in Parallel.
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> **(1) General.** Aluminum, copper-clad aluminum, or copper conductors,
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> for each phase, polarity, neutral, or grounded circuit
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> shall be permitted to be connected in parallel
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> (electrically joined at both ends)
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> *only in sizes 1/0 AWG and larger*
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> where installed in accordance with 310.10(H)(2) through (H)(6).
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Rank by total cost of install.
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## Complexity to Ignore
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### Conductor Material
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Tinned copper and copper-clad aluminum conductors
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can be assumed out of scope.
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## Complexity to Respect
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Wire and EGC conductors are usually assumed to match,
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but it is sometimes preferable to use a copper EGC
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with high-amp aluminum parallel feeds. |