BASIC NEC CODE RULES AND DESIGN PRACTICE

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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