All about Electrical Grounding/Earthing

All about Electrical Grounding/Earthing 

The process of instantaneous discharge of electrical energy directly to the ground with the help of low resistance wire is known as electrical grounding. Electrical grounding is carried out by connecting the non-current carrying part of the device or the neutral of the supply system to the ground.

Mostly, galvanized iron is used for grounding. Earthing provides the simple path of leakage current. The short circuit current of the equipment passes to the ground which has no potential. Thus, it protects the system and equipment from damage.

Types of electrical grounding

Electrical equipment consists of 2 non-current parts. These parts are neutral to the electrical system or frame of the equipment. From the grounding of these two non-carrying electric parts, the grounding of the electrical system can be classified into two types.

Neutral grounding

Equipment grounding.

Neutral grounding

In neutral grounding, the system is connected directly to earth. Neutral grounding is also called system grounding. This type of grounding is mostly provided for the system which has a star winding. For instance. Neutral grounding is provided in the generator, transformer, motor, etc.

equipment grounding

This type of grounding is provided for electrical equipment. The non-current carrying part of the equipment such as its metal frame is connected to the ground with the help of connecting wire. In the event of any failure of the equipment, the short circuit current passes through the ground with the help of the wire. Thus, protecting the system from damage.

The importance of grounding

Grounding is necessary for the following reasons

Grounding protects personnel from short circuit current.

Grounding provides the easiest path for short circuit current to flow even after insulation failure.

Grounding protects the equipment and personnel from high voltage surges and lightning discharges.

Earthing can be done by electrically connecting the electrically involved parts of the installation to some electrical conductor system or electrodes placed near the soil or below ground level. The grounding mat or electrode below ground level has a flat iron riser through which all the non-current carrying metal parts of the equipment are connected.

elctrical-earth-1 When a fault occurs the fault current will flow from the equipment through the earthing system to earth thus protecting the equipment from fault current. At the time of the fault, the ground mat conductors rise to a voltage equal to the resistance of the ground mat multiplied by the ground fault.

Electrical grounding -2 is called the assembly connected to the grounding. The metal conductors connecting the mounting parts with the grounding are called electrical conductors. Grounding and grounding together is called system grounding.