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Why is the size in mm for a 2/0 bare conductor different in the first column of Table 8 in Chapter 9 than the column for overall size? I never noticed before because I usually look for the inches and not metric.
Hey Claudia thanks for your question. It's all about the air spaces, not a metric issue. The values in Col 2 are based on the metric equivalent of the circular mil area of the conductor material. Those are used for sizing the conductors. The overall column values are based on the outside diameters of all the strands, which includes the air spaces between the strands. Those are used for sizing the raceways.
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