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conductor-sizing.md

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