BASIC NEC CODE RULES AND DESIGN PRACTICE

Wire Ampacity and Size Maximum loading for any branch circuit is 80% of rating of circuit for ampacity of wire for any load. NEC 220-2, use NEC 310-16 for ampacity. ... 250 250 MCM 200. 300 350 MCM or 2-1/0 Parallel 240. 350 500 MCM or 2-2/0 Parallel 280. 400 600 MCM or 2-3/0 Parallel 320 ... ................
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