What role does earthing play in electrical installations?
Directs fault current to ground
Earthing is a protective measure: the exposed metallic parts of equipment are connected to the general mass of the earth through a conductor of very low resistance.
During normal operation these metal parts stay dead, but a fault, such as a live wire touching the casing, can make the body live and dangerous to anyone who touches it.
The earth path offers far lower resistance than a human body, so the fault current preferentially flows to ground through the earth conductor rather than through a person.
This heavy fault current also causes the fuse to blow or the circuit breaker to trip quickly, isolating the faulty circuit from the supply.
Earthing does not reduce the working voltage supplied to devices; the supply voltage is fixed by the transformer, not by the earth connection.
Nor does it increase device power or store excess electricity; earth is a sink for fault current, not a source or a store of charge.
Hence, the answer is Directs fault current to ground.
Similar Questions
Where should an ammeter be connected in a circuit to measure current accurately?
A magnetic core carries a magnetic flux of 0.02 Wb. If the cross-sectional area of the core is kept the same, which action will most directly increase the magnetic flux?
A copper wire has a resistance of 3 Ω and carries a current of 4 A. What is the power loss in the wire due to heating?
Which type of current changes both magnitude and direction at definite intervals?
What value of inductor should be connected in parallel with a series combination of 4 H and 2 H so that the effective inductance of the circuit is 3 H?
Two magnetic paths are made of the same material and have the same cross-sectional area. Path X has length 0.1 m, and Path Y has length 0.3 m. Which statement is correct about their reluctances?
What does the magnetic permeability of a material represent?
What is the SI unit of magnetic flux?
Why is an ammeter always connected in series with the load while measuring current in a circuit?
A 2 kW electric heater operates for 45 minutes on its rated supply. How much electrical energy does it consume?
Important Questions from Basic Electricity
What is the name of this electrical wire joint?
How the OLP is connected with Refrigeration circuit of a refrigerator?
Which type of relay is used with window type air conditioner?
What is the use of Thermo-Volume Switch?
What is the relation between voltage and ampere?
