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Wire Size for Required Current

Only one of many, refer to article 310 of NEC:

Wire size is determined by the load computed for the branch circuit. The load tells you the size of wire to use and the size of the overcurrent protection to use. Use only 80% of the maximum current capacity of the wire and the overcurrent protection (breaker or fuse).

            TYPES:fepw,rh,rhw,thw,thwn,xhhw,use,zw
              Check asterisk note table 310-16
                **************************
                |  Wire Size  | Current  |
                |    Awg      | Max-Amp  |
                |------------ |----------|                                                  
                |    14       |    15    |
                |    12       |    20    |
                |    10       |    30    |
                |     8       |    50    |
                |     6       |    65    |
                |     4       |    85    |
                |     3       |   100    |
                |     2       |   115    |
                |     1       |   130    |
                |   1/0       |   150    | 
                |   2/0       |   175    |
                |   3/0       |   200    |
                |   4/0       |   230    |
                |   250 mcm   |   255    |
                |   300 mcm   |   285    |
                |   350 mcm   |   310    |
                |   400 mcm   |   335    |
                |   500 mcm   |   380    |
                |   750 mcm   |   475    |
                **************************
  
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