What Is 4 Core Electrical Cable?

Normally, because of the heavy loads involved, 3-phase cables aren’t common in residential and housing applications. However, these are standard for other applications, such as high-rise rooming complexes, commercial and industrial applications, where the use of 4 core electric cable is essential.

For three-phased heavy-duty power applications, you may see cables such as 240mm 4 core cable used by electricians. The 4 core cable used here has four conductors, where each of the 4 core cable colours has a specific function.  Three of which are live (L1, L2 and L3), with one acting as neutral. These colour-coded cores are individually covered in PVC insulation to keep them separate, grouped into a single 4-core cable and sheathed in an inner layer.

There are various types of 4 core electrical cable available. A common one is steel wire armoured cable (SWA), which is also called 4 core SWA cable. In this version, the cable has an additional layer of protection built into it. The inner sheath is covered in another layer – typically made from galvanised twisted steel wire. To complete the 4 core armoured cable, an outer layer of insulation is added which protects the SWA coating.

Another unique characteristic of 4 core copper cable is the insulation used when manufacturing the cable. You might see heavy-duty cables, such as 35mm 4 core armoured cable on the side on roadways and bridges. These have insulations made from material known as XLPE. The “XL” denotes Cross-linked – which identifies a technique of manufacturing the 4 core SWA cable. And then, the “PE” stands for Polyethylene – which is the material used in producing the insulation. Such cables are called 4 core XLPE cable.