Earth Cable

  • According to IEC and GB Standard
  • Flame Retardant Cable
  • Approved by CCC, ISO, BV, SGS
  • Yellow-Green

The earth cable keeps electricity flowing into your home or business. The earth cable is also called the ground wire or ground cable. It’s most often in the form of a copper wire buried in the ground.

Conductor: Copper 

Insulation: PVC

Color of outer sheath: Yellow-Green

Voltage: 450/750V

Earth Cable: Get more out of your cable system

Earth cable is in the electrical system or electronic equipment, connected to the earth, the shell, or the reference potential of the neutral wire. Earth wire is essential in electrical safety and equipment performance, which determines the safety of electric equipment and personnel.

what is earth cable

What is earth cable?

The earth cable refers to wires within the electric circuit that provides a safe pathway to the ground for excess current in an electrical fault.

The primary purpose of an earth cable is to provide a safe pathway for excessive current in case of an electrical fault. Unlike any other conductor present within a circuit, any electrical current flowing through it is not affected. Hence, all excess current will flow through this conductor and into the ground, thus protecting any person or property from being harmed by the current.

Earth cables are usually made from copper or aluminum and can be found in industrial buildings. When installing electrical cables, you also need earth cables. Earth cables are usually colour-coded, so they can be identified easily during installation and maintenance work. The colour code for earth cables varies from country to country, but they are generally green with yellow stripes. We called it yellow-green. 

The earth cable has an insulated copper wire with yellow-green sheath. It’s also known as the safety earthing wire or ground wire.

What are earth cables used for?

Earth cables are used for the protection of human life, lightning protection, and to ensure the regular operation of electrical equipment. They are mainly composed of power cables, grounding cables, lightning protection wires, and other components.

1, protection of human life

Earth cable as a building and the earth connection, you can conduct the current to the ground to avoid electrocution.

2, lightning protection

Lightning is a sudden discharge of electricity in the atmosphere caused by friction between ice crystals in clouds or different objects. The high buildings are vulnerable to lightning but connected to the ground, and then the current can be conducted along the ground wire underground buildings.

3, To ensure regular operation of electrical equipment

Electrical equipment is susceptible to lightning, affecting the operation of electrical equipment through the ground wire will conduct current underground so can ensure the operation of electrical equipment.

How to calculate earthing cable size?

Many of the earthing conductors are used for underground and other equipment. The most popular size is a 16mm earth cable. The basic requirements for earthing conductor are as follows:

  1. The length of the earthing conductor should be at least 30 meters from the end of the grounding point to the ground terminal of the equipment;
  2. The type of connection between the earthing conductor and ground terminal should be reliable;
  3. The resistance of the earthing conductor should not exceed 0.5 ohms per meter or 1 ohm at any point along its length;
  4. The grounding points should be within 2 meters from each other;
  5. The resistance of the earth in moist soil is less than that in dry soil, but it can not be ignored because there may be moisture in some areas due to rain or flooding。

In this example, we will use a PE(Sqmm) = 1.5 x √ (I(Fault-A)2 x t(s)) / k.

If you want to calculate the size of earthing conductor, there are three things that you need to know:

  • Earthing current (I). In this case, I is 200A, so 200A
  • Earthing resistance (R). The resistance of earth is 0.5 ohm, so R = 0.5 ohm
  • Earthing time (t). The time is 0.5 s, so t = 0.5 s

The formula for calculating the size of earthing conductor is as follows:

PE(Sqmm) = 1.5 x √ (I(Fault-A)2 x t(s)) / k

Why earth cable is important?

 The earth wire is not strictly necessary for the operation of a device, but it is still an important feature. This wire allows electrical current to travel if the typical paths aren’t available.

If a device has a short circuit, the welding earth cable will provide a safe means for electricity to flow out of the device and into the ground. This prevents the short circuit from becoming more prominent and causing more damage. If there’s no earth wire in place, there will be nowhere for any excess current except through other circuits or parts of the device itself.

The twin and earth cable also protects against surges in voltage caused by lightning strikes or electrical storms. In these situations, large amounts of energy are transferred from one point in the electric power grid to another. It can cause high voltages on household wiring systems that aren’t designed for them. If we don’t install grounding cables, these voltages could potentially cause severe damage to electrical devices connected to them.


The earth cable is an essential part of a building’s electrical system. It is used to protect the building from damage caused by lightning strikes and surges in voltage. The cable also enables the electrical system to be grounded, which helps prevent fires and electrocution.

Many types of earth cables are available, so it is crucial to choose the right kind for your needs.

ZW Cable is a leading China supplier of earth cable, which is made of excellent materials. Our earth cable has wide applications in power plants, chemical plants, mines, and other industrial installations where the grounding system is required. If you want to choose reliable suppliers who can offer you the best earth cable price and be your long-term partner, please feel free to contact us!