BASIC NEC CODE RULES AND DESIGN PRACTICE - US Forest …

If circuit is loaded up to ampacity and distance to load is around 100 feet, then voltage drop will govern and will require larger wire size. If more than 3 phase wires are in one conduit, then wires must be derated according to Note 8, after Table 310-19 as follows: TABLE 1. Number of Conductors Percent of Values in 310-16 *1-3 80 *4-6 80 ................
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