Electrical Code NEC-Table310-16

Summary: Table 310-16. Allowable Ampacities of Insulated Conductors Rated 0 through 2000 Volts 60° to 90°C (140° to 194°F) Not More Than Three Current-Carrying Conductors in Raceway or Cable or Earth (Directly Buried), Based on Ambient Temperature of 30°C (86°F).

Allowable Ampacities of Insulated Conductors

Although this is the most common table used to determine wire size, this is just one example.

Based on NEC Table 310-16 as shown in the NEC Table 310-16 below the temperature rating of the insulation has much to do with how much electrical current the wire is designed to withstand.

Although this table is true and accurate, many times the wire type is not known. There are also instances where more than one type of wire is used on a circuit. This is why it is best to use this default chart to determine the capacity of the wire sizes listed below
.
Please Note: This table is for Copper Wire Only:

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