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Electrical Conductors
The inductance, L , per core of a 3-core cable or of three single-core cables comprises two parts namely the self-inductance of the conductor and the mutual inductance with other cores. The fo…
The tables below indicate the electrical and physical properties of metals commonly used in the manufacture of electric cables in the electrical industry. Familiarity with these properties is requi…
A coaxial cable consists of four basic parts: Inner conductor (center conductor) Outer conductor (shield) Dielectric, which separates the inner and outer conductors Jacket, which is the outer …
For the purpose of calculating voltage drop within a cable, the table below gives the reactance and resistance values for Copper and Aluminium cables: Values for Copper Cables …
Often times in the application of electrical cables, we neglect the thermal characteristics of the polymers used in the cable insulation. Here is a list of the temperature range each of the common…
As already discussed in Ampacity of a Conductor , the ampacity of a conductor depends on temperature. Any change in ambient temperature affects the ampacity of an electrical cable. When this happen…
To calculate the nominal diameter of any concentric-lay-stranded conductor made from round wires of uniform diameters, multiply the diameter of an individual wire by the applicable factors listed b…
The DC resistance of copper wire increases with increasing temperature in accordance with the formula: On the basis of the above formula, we now generate a table of correction factors for copper…
The capacity or rating of a transformer is limited by the temperature that the insulation can tolerate. The life of a transformer can be extended by making sure it is not operated over and above t…
A conductor offers a greater resistance to the flow of alternating current(AC) than it does to direct current(DC). The magnitude of the increase is usually expressed as an “AC/DC ” ratio. The reaso…
Wire size is expressed in circular mils(CM). A mil is one-thousandth of an inch. In the United States, the American Wire Gauge is used. It is a scale of even numbers that start with the number 40 a…
Ampacity is the current carrying capacity of a conductor. Ampacity calculation should take into account natural variables such as solar warming, wind and air density, viscosity, and thermal conduct…
The DC resistance of a conductor or cable is that defined by ohms law. It is a function of many factors including temperature which greatly affects the resistance of a given material. Copper and Al…