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Wire size table from the Digest 177 - Conductor ampacity based on the 2014 National Electric Code

Issue:
What is the rating of the wire?
How much current can the wire carry?
What is the amp rating for each size of wire?
How do I size the wire?
NEC Table 310.15(B)(16)[Formerly 310.16]
Wire size table

Product Line and Environment:
This FAQ applies to installed products under the jurisdiction of the National Electric Code

Resolution:
The National Electric Code has information about ampacity rating of various types of conductors. With permission, some of this is reprinted on the inside cover of the Square D Digest. The attached file is a copy of that page from Square D Digest 177.

Example using NEC Table 310.15(B)(16)
  • The rating of 3/0 Copper wire, 75C, type THHW is 200A
  • The rating of 3/0 Aluminum wire, 75C, type THHW is 155A
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