EGC for Parallel Raceways (NEC 250.122(F))
The paragraph egc-upsize-proportional's sibling never covered: (B) was implemented, (F) was not. Each raceway of a paralleled feeder needs its OWN full-size EGC sized to the WHOLE circuit's device - the EGC is not divided among sets the way the ungrounded conductors are. A 400 A feeder in 2 raceways takes two #3 copper, not the #6 that sizing from 200 A would give. A ground fault returns through THAT raceway's EGC alone. Flags the 2026 NEC revision, which changes the answer.
Formula and source
Each parallel raceway carries a full-size EGC sized from Table 250.122 to the WHOLE circuit's overcurrent device rating; total EGC runs = number of raceways. The EGC is not divided among the parallel sets.
NEC 250.122(F), equipment grounding conductors for conductors in parallel, by section number - the 2023-and-earlier rule; no table is reproduced here because the sizing is delegated to this catalog's existing egc-sizing model.
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