A Guide to Choosing the Right Earthing Strip
Choosing the right earthing system for your power supply is essential to protect both your property and the property residents. The purpose of earthing is to connect the non-current-carrying parts of electrical apparatus to the general mass of earth so that an immediate discharge of electrical energy is allowed.
A good earthing system would:
- Safely dissipate short-circuit currents
- Ensure that users are not electrocuted by blowing fuses
- Not let the conductive parts of electrical equipment reach dangerous voltages
- Prevent excessive currents or voltages from flowing through appliances or equipment by maintaining the voltage in an electrical system
Types of Earthing Systems
T = Direct connection to the Earth I = Isolated N = Neutral S = Separate C = Combine
TT Earthing System – In this type of earthing system, the supply source is directly connected to the earth, as well as the installation metalwork. This means that the earth’s mass will be the return path in the event of an overhead line failure.
IT Earthing System – Substations and generators use the IT Earthing System for power distribution. There is no connection between the distributor system and the earth. Given a fault between the phases and the earth occurs, the system continues to operate without interruption.
TN-C Earthing System – A TN-C earthing system combines the neutral and protective earth into a single conductor. All exposed and conductive parts of the installation are connected to the PEN conductor.
TN-S Earthing System – The TN-S earthing system has a single neutral-to-earth connection, placed next to the supply transformer. The Ground Conductor and Neutral Conductor are separate throughout the distribution system. Earthing terminal or the main conductor of the installation connects all the exposed conductive parts of the installation.
When choosing earthing strips, it is important to consider the following factors:
Size Material Design Environment
Ideally, the strip should be made of copper, aluminum, or galvanized iron (GI). Flexibility of the strips is another determining factor, it makes them suitable for a wide variety of applications. In general, the thickness of an earthing strip ranges between 3 and 6 mm, while the width is between 15 and 100 mm. Furthermore, the thermal and electrical conductivity of the earthing strip should also be good. Lastly, suitable for areas with rocky soil conditions, earthing strips have a long lifespan and require little to no maintenance.
For more information, contact www.pinaxsteel.com