Why white powder is used inside Electrical Cables?

You may have noticed some white powder is used in high current carrying electrical cables and questions might have arisen in your mind why they are used. So in this article, we are going to know why white powders are used inside electrical cables, what is the name of these powders.

According to current carrying capacity and applications of electrical cables, different types of powder are used such as Talcum Powder, Magnesium Oxide (MgO) Powder, Swell-able Powder, Chalk Powder, etc.

Talcum Powder in Electrical Cables

Talcum Powder is used in some low current-carrying cables such as computer power cable to make it flexible, to stop the internal wires from getting stuck to the outer rubber casing. When a cable is used over a long period of time, its outer rubber gets sticky and can be broken down. So to prevent this problem talcum powder is used in some electrical cables.

Magnesium Oxide Powder in Electrical Cables

Magnesium Oxide Powder is used in high current carrying cables and Mineral Insulated (MI) cables. Magnesium Oxide Powder has two very useful properties that:

• high thermal conductivity,
• low electrical conductivity.

Magnesium Oxide Powder offers a lot of features and advantages in an electrical cable which are given below:

• When high current flows through a cable, heat is produced which can damage the cable. Due to the high thermal conductivity of Magnesium Oxide Power, the heat is conducted from inside of the cable to the outside and the damage of the cable from heat is prevented.
• Due to low electrical conductivity property, Magnesium Oxide Powder provides good electrical insulation.
• Magnesium Oxide Powder provides good lubrication to electrical cables.
• Magnesium Oxide Powder makes electrical cables fireproof.
• Magnesium Oxide Powder makes electrical cables flexible.

Swell-able Powder in Electrical Cables

Swell-able Powder is used in electrical cables to block the water and to eliminate the moisture inside cables. This powder forms a gel-like material when contacting with water and blocks the flow of water inside the cable. This powder swells and expands to block the water permanently.

Chalk Powder in Electrical Cables

Chalk Powder is used in some cables to provide fire resistance. To prevent cores inside a cable from fire, chalk powder is used in some electrical cables.

The original article can be seen here.