Allowable Ampacities of Insulated Conductors Rated 0-2000 Volts As Excerpted from the 2002 National Electrical Code Ampacities of Not More Than Three Current-Carrying Conductors in Raceway, Cable or Earth.

Temperature Rating of Conductor [See Table 310.104(A).] Size AWG or kcmil 60°C (140°F) 75°C (167°F) 90°C (194°F) 60°C (140°F) 75°C (167°F) 90°C (194°F) Size AWG or kcmil Types TW, UF Types RHW, THHW, THW, THWN, XHHW, USE, ZW Types TBS, SA, SIS, FEP, FEPB, MI, RHH, RHW-2, THHN, THHW, THW-2, THWN-2, USE-2, XHH, XHHW, XHHW-2, ZW-2 ...

In these AWG gauge charts, most common gauge values show the different characteristics of wire such as its diameter, area, ampacity, resistance, current density, fusing current and temperature ratings etc.

Namely, the current carrying capability of a wire – ampacity – depends on three key factors: Size of the wire (expressed as AWG or kcmil). On the left side of the NEC 310.16 table (further on), we see different wire cross-sections (AWG or kcmil). The thicker the wire, the more amps it can carry.

Allowable Ampacity Tables NFPA 70: NEC - 2023 Notes: 1. Section 310.15(B) shall be referenced for ampacity correction factors where the ambient temperature is other than 30°C (86°F). 2. Section 310.17 shall be referenced for conditions of use. *Section 240.4(D) shall be referenced for conductor overcurrent protection limitations, except

For ambient temperatures other than 30°C (86°F), multiply the allowable ampacities shown above by the appropriate factor shown below. *See 240.4(D). Reprinted with permission from NFPA 70-1999, National Electrical Code ®, Copyright © 1998, …

Ampacity based on NEC ® Table 310.15(B)(16) (formerly Table 310.16) Allowable Ampacities of Insulated Conductors Rated Up to and Including 2000 Volts, 60° through 90°C (140° through 194°F), Not More Than Three Current-Carrying Conductors in Raceway, Cable, or Earth (Directly Buried), Based on Ambient Temperature of 30°C (86°F).

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• Shall use the ampacity from the 60 ° C Column – Larger than #1 or over 100 amps • Shall use the ampacity from the 75 ° C Column – The 90 ° C ampacity can be used for corrections only. • Ambient Temperature • Number of Conductors

Allowable ampacities of single insulated conductors Rated 0 - 2000 Volts, in free air, based on ambient air temperature of 30°C (86°F). For ambient temperature other than 30°C (86°F), multiply the allowable ampacities specified above by the appropriate correction factor shown below.