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Wednesday, April 12, 2023

Question:

Hi code friends. In reference to NEC 250.122(B), as it applies to increasing conductor sizing to compensate for voltage drop, it states that the grounding conductor shall be increased in size proportionately to the increase in area of the ungrounded conductors. For example, the copper ungrounded and grounded conductor in a 120-volt, 20A circuit are increased from #12 to #6 to compensate for voltage drop, since the required equipment grounding conductor for a 20A OCPD is a #12 copper conductor would the equipment grounding conductor also need to be increased to a #6 AWG? Thanks, Dennis DiPasquo
A

Answer:

Hello Dennis, thank you for participating. Your example is correct, the equipment grounding conductor would also need to be increased to a #6. The ungrounded and grounded neutral conductor are both being increased from a #12 to a #6. In your example the required copper equipment grounding conductor for a 20A OCPD is #12 per Table 250.122. This happens to be the same size as the ungrounded copper conductor (before the increase), which makes the increase the same for both conductors.  

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