The engineering calculations for an 800-ampere service-entrance call for two 500-kcmil copper conductors per phase connected in parallel. The neutral conductor calculations show that the neutral...

The engineering calculations for an 800-ampere service-entrance call for two 500-kcmil copper conductors per phase connected in parallel. The neutral conductor calculations show that the neutral conductors need only be 3 AWG copper conductors. The riser diagram shows two rigid metal conduits, each containing three 500-kcmil phase conductors and one 1/0 AWG neutral conductor. Why is the neutral conductor sized as a 1/0 AWG, or is this a mistake?
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