Different types of conductors
An electric conductor is a material that allows the flow of electric current to pass through. The electric conductivity will depend on the actual material of the conductor. If the material allows high mobility of free electrons this will make them great conductors of electricity.
Metals are some of the best conductors because there are spaces between their atoms which allows electrons to move. Of all the materials, the top three are silver, copper and aluminum.
Silver is known to be the best conductor of electricity but it is not widely used for economic reasons. It is only used for special equipment like satellites.
Copper, though not as high as silver, also has high conductivity. In fact, the official point of reference for conductors is the International Annealed Copper Standard (IACS). The most common grade of copper is ETP (electrolytic-tough pitch) copper. This is the metal used in wires, cables, busbars and motor windings. The conductivity of this copper is 101% IACS.
Aluminum only has 61% of the conductivity of copper but it is the preferred material for building wires because of the low cost. Aluminum has higher conductivity when compared to copper by weight but it requires a compatible connector to avoid the formation of resistive oxide within connections. When used in building wiring, it slowly deforms under load and that leads to the loosening of device connections. When it has the right connector and is installed properly, it works well for low voltage distribution (e.g. service drops, buried cables).
There are certain nonmetals that can also be conductors of energy like water, graphite, concrete or glass. These are less conductive compared to metals but under the right circumstances, they can become effective conductors.
Pure water (H2O) is not a conductor but when it becomes dirty (or mixed with other elements like salt), electricity can flow through it. Most of the water on Earth is actually “dirty water” because it has other compounds added to the pure water. Other liquids, oil or organic compounds, cannot conduct energy because of their composition.
Glass is usually an insulator but when it is heated, it can become a conductor. This is in contrast with metals that become better conductors when cooled but less when heated.
AAC, AAAC, ACSR Aluminium Conductors
AAC, AAAC, ACSR form part of the family of Overhead Conductors, Transmission Conductors and Power Distribution Conductors. These cables are formally known as All Aluminium Conductor (AAC), All Aluminium Alloy Conductor (AAAC) and Aluminium Conductor Steel Reinforced (ACSR). These overhead aluminium conductors are used as power transmission and distribution lines. All aluminium conductors are made up of one or more strands of aluminium wire depending on the specific application.
Our range of aluminium overhead conductor cables includes:
AAC–ASTM-B All Aluminium Conductor
AAC are a refined Aluminium stranded conductor with a minimum metal purity of 99.7%. It is principally used in urban areas where spacing is short and the supports are close. It can be used in coastal regions owing to its high degree of corrosion resistance and is also used extensively within the Railway and Metro industries.
AAAC-ASTM-B All Aluminium Alloy Conductor
AAAC are used as a bare conductor cable on aerial circuits that require a larger mechanical resistance than the AAC and a better corrosion resistance than the ACSR. The sag characteristics and the strength-to-weight ratio of the AAAC conductor cable is better than both AAC and ACSR.
ACSR-ASTM-B Aluminium Conductor Steel Reinforced
ACSR are available in a range of steel contents ranging from 6% to 40% for additional strength. The higher strength ACSR conductors are commonly used for river crossings, overhead earth wires, and installations involving extra-long spans. The ACSR conductor can, against any given resistance, be manufactured to different tensile strengths, so a high tensile strength combined with its lightweight properties means it can cover longer distances with fewer supports. Due to the greater diameter of the ACSR conductor, a much higher corona limit can be obtained which is advantageous on high and extra high voltage overhead lines.
