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40 AWG Wire

40 AWG (American Wire Gauge) wire specifications: 0.0799 mm diameter, 0.005 mm² area. Resistance, weight, and common uses.

Diameter
0.0799 mm
0.003145"
Area
0.005 mm²
10 cmil
Ampacity (Cu)
—A
75°C insulation
Resistance (Cu)
3440.8696
Ω/km at 20°C

40 AWG — Complete Specifications

Diameter0.0799 mm · 0.003145" · 3.14 mils
Cross-sectional area0.005 mm² · 10 circular mils
Resistance (copper, 20°C)3440.8696 Ω/km · 1048.777 Ω/1000ft
Resistance (aluminum, 20°C)5289.0397 Ω/km · 1612.0993 Ω/1000ft
Ampacity — copper 60°C— A
Ampacity — copper 75°C— A
Ampacity — copper 90°C— A
Ampacity — aluminum 75°C— A
Weight (copper)0.045 kg/km · 0.03 lbs/1000ft
Weight (aluminum)0.014 kg/km · 0.009 lbs/1000ft
Closest metric size0.0 mm²
Skin depth at 60 Hz8.531 mm

Common Uses for 40 AWG Wire

Compatible Insulation Types

TypeTemperatureDescription
PVC 60-105°C General purpose insulation
Teflon (PTFE) 200°C High temperature applications
Silicone 200°C Flexible, high temperature
Enamel 155-220°C Magnet wire coating

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