THHN and THWN is a multi-purpose building wire used in conduit and cable trays for service, feeders and branch circuits in commercial and industrial applications. It is also used as a conductor in NM-B, UF-B, SER, SEU and MC. Southwires THHN is rated for 600-Volt and has a heat capacity of up to 90Deg.
Type THHN/THWN-2 building wire is intended for general purpose applications as defined by the National Electrical Code (NEC).Type THHN-THWN-2 is permitted for new construction or rewiring for 600-volt applications. Applications requiring Type THHN or THWN-2, the conductor is appropriate for use in wet or dry locations at temperatures not to exceed 90Deg or not to exceed 75Deg in oil or coolants. Applications requiring Type MTW conductor is appropriate for use in dry locations at 90Deg, or not to exceed 60Deg in wet locations or where exposed to oils or coolants. Applications requiring Type AWM conductor is appropriate for use at temperatures to not exceed 105Deg in dry locations.
Underwriters Laboratories Standards UL-83, UL-1063, UL-758
AWM Spec 1316, 1317, 1318, 1319, 1320, 1321
ASTM Stranding Class B3, B8, B787
Federal Specification A-A-59544
Canadian Standards Association C22.2 No. 75
NEMA WC70/ICEA S-95-658
Institute of Electrical and Electronics Engineers
Size: 12 AWG
Number of Strands: 19
Cross Section Area (mm2): 3.31
PVC Insulation Thickness (Conductor): 0.380 mm / 0.015 inches
Nylon Jacket Thickness: 0.100 mm / 0.004 inches
Outside Diameter: 3.23 mm / 0.127 inches
Allowable Ampacity: 20 Amps at 60degC / 20 Amps at 75degC / 20 Amps at 90degC