Search results
Results from the WOW.Com Content Network
This means that all pure copper (Cu) wires (which have not been subjected to distortion of their crystalline structure etc.), irrespective of their shape and size, have the same resistivity, but a long, thin copper wire has a much larger resistance than a thick, short copper wire. Every material has its own characteristic resistivity.
Also called chordal or DC resistance This corresponds to the usual definition of resistance; the voltage divided by the current R s t a t i c = V I. {\displaystyle R_{\mathrm {static} }={V \over I}.} It is the slope of the line (chord) from the origin through the point on the curve. Static resistance determines the power dissipation in an electrical component. Points on the current–voltage ...
Skin effect reduces the effective cross-section of the conductor and thus increases its effective resistance. At 60 Hz in copper, skin depth is about 8.5 mm. At high frequencies, skin depth becomes much smaller. Increased AC resistance caused by skin effect can be mitigated by using a specialized multistrand wire called litz wire. Because the ...
The resistance of copper wire is approximately 1 Ω / 1000 ft for 10 AWG, 10 Ω / 1000 ft for 20 AWG, 100 Ω / 1000 ft for 30 AWG, and so on. [5]: 27 For an arbitrary gauge n, it's approximately 10 n/10 Ω per 10 000 ft.
With high-frequency currents, the proximity effect and skin effect cause the current to be unevenly distributed across the conductor, increasing its effective resistance, and making loss calculations more difficult. Litz wire is a type of wire constructed to force the current to be distributed uniformly, thereby reducing Joule heating.
Also, comparatively, more copper wire can fit in a given conduit than conductors with lower conductivities. This greater wire fill is a special advantage when a system is rewired or expanded. [17] Copper building wire is compatible with brass and quality plated screws. The wire provides connections that will not corrode or creep.
Sometime around 1913, several copper samples from 14 important refiners and wire manufacturers were analyzed by the U.S. Bureau of Standards. The average resistance of the samples was determined to be 0.15292 Ω for copper wires with a mass of 1 gram of uniform cross section and 1 meter in length at 20 °C. In the United States this is usually ...
In some applications wire sizes are specified as the cross sectional area of the wire, usually in mm 2. Advantages of this system include the ability to readily calculate the physical dimensions or weight of wire, ability to take account of non-circular wire, and ease of calculation of electrical properties.