All Aluminium Conductor (AAC) – Despite having a good conductivity, because of its relatively poor strength, AAC has limited use in transmission and rural distribution lines. However, AAC can be seen in urban areas for distribution where spans are usually short but higher conductivity is required.
Aluminium Conductor Steel Reinforced (ACSR) – ACSR with higher steel content is selected where higher mechanical strength is required, such as river crossing. ASCR conductors are very widely used for all transmission and distribution purposes.
All Aluminium Alloy Conductor (AAAC) – Because of AAAC’s lighter weight as compared to ACSR of equal strength and current capacity, AAAC may be used for distribution purposes. However, it is not usually preferred for transmission. Also, AAAC conductors can be employed in coastal areas because of their excellent corrosion resistance.
The insulation consists of placing an insulating coating on the conductor to prevent current leakage. They are classified into two large groups: thermoplastic and thermoset.
They are most common in the manufacture of electrical cables are:
In some cases, the cables may have metal shields.
Old BS 3-Phase Colours | New BS 3-Phase Colours | |
Phase 1 | Red | Brown |
Phase 2 | Yellow | Black |
Phase 3 | Blue | Grey |
Neutral | Black | Blue |