Why does electricity have to be earthed?

Answer 1

It is well known that most electricity systems need to be earthed and this practice probably started in the very first days of electrical experiments. Then, as now, static was discharged by connection to a plate which was in contact with the general mass of earth. The practice has continued and been progressively developed, such that connections to earth occur at almost every point in the electricity system. This includes the generating station, the lines and cables which distribute electricity and the premises at which it is used. The need for such a connection is sometimes enshrined in legislation. For example in the UK, the Electricity Supply Regulations 1988, clause 5(1), require all systems (i.e. Generation, Transmission and Distribution) to be earthed at one point. This does not actually extend to the installation within premises and whilst it is still the most common arrangement to earth such installations, the standards (for example via BS 7671:1992, Amendment 1, 1994, Requirements for Electrical Installations) allow for certain unearthed arrangements.

Whilst earthing forms an intrinsic part of the electricity system, it still remains in general a misunderstood subject and is often referred to as a "black art" - even sometimes by well qualified engineers. In recent years there have been rapid developments in the modelling of earthing systems at power frequencies and higher, mainly facilitated by computer hardware and software. This has increased our understanding of the subject at the same time that the design task has become significantly more difficult and emerging standards are requiring a more detailed, safer design. There is thus an opportunity to explain earthing concepts more clearly and a need for this to be conveyed to earthing system designers and installers so that a greater understanding may be gained.

By earthing, we generally mean an electrical connection to the general mass of earth, the latter being a volume of soil/rock etc., whose dimensions are very large in comparison to the electricity system being considered.

Answer 2

In AC power, there are two wire call live and neutral. Neutral is usually grounded at the power station or sub station.When you switch on a light, current from live wire flow through light bulb and to neutral which will return to ground via power station.
Almost all home appliances which has metal body need to connect to ground wire provide by power supply company.This ground wire is actually not neutral wire.Neutral wire has the same current as live wire while ground wire has very little current (less than 30 mA) called leakage current.If the current difference between live and neutral wire is more than 30mA, power supply will be cut off by circuit breaker called ELCB or RCCB.So with the protection of these circuit breakers you will not be electrocuted easily.

ELCB stands for Earth Leakage Circuit Breaker
RCCB stands for Residual Current Circuit Breaker
Hope you get the answer.

Answer 3

It doesn't have to be earthed. It is earthed for safety, if there is a fault rather than travelling through someone who touches the faulty appliacne it will travel via the earth route provided. Electric power lines are not earthed, you can hang on them if you wanted, you would of course be live but this wouldn't be an issue until you were earthed, the current would then be able to travel through you and in all likelihood kill you.

Answer 4

As far as my understanding is that A currents natural route is to the ground and anything that is conductable it will pass through to get there so earth links on plugs and electrical equipment form the easiest route for the current to pass through thus making it safer for the user as it will take the easiest route rather than pass through the person. In some cases the user being electrocuted is receiving only part of the current the rest going through the earth link or wire making it less life threatening - don't try it, its not nice being electrocuted!

Answer 5

Power suppliers ground (EARTH) one of the wires leaving the power station. This cable is called the "NEUTRAL" The other cable is called the "LIVE" The two cables carry the main load.
If you accidentally touch the neutral and the ground (EARTH) you will NOT be electroculated, as the voltage would only be below 10
However if you touch the live you will get shock or worse.
Therefore it is a SAFETY feature

Answer 6

Electricity will always naturally try to find its way to earth, it will do this by the easiest route possible, if an appliance running dangerous voltages is not earthed (i.e. providing an easy route to earth) and it shorts out, the electricity will follow the next easiest route, if you touch the appliance you form the next easiest route to earth, so it is for safety reasons

Answer 7

regrettably its no longer sparkling out of your question the position you're positioned yet i'm guessing uk as water mains/ provider replace is the in component in the present day.This being so it truly is a call for of the regulations (electric powered) that each and each and every one metalwork ie pipes are appropriate to earth so if there is gasoline getting into your position there should be a simular connection close to to the gasoline meter.If the relationship on the water pipe is above the provide up faucet ie on the homestead section then that ought to need to educate it truly is real and if its below the provide up faucet its incorrect and is amazingly in all probability a marginally previous wiring equipment(this became replaced over 30 years in the past)in case your hose has been rewired in a minimum of the perfect 30 years it will be maximum acceptable proper yet once you've any doubts get a sparky in to envision for you and if it needs doing he will be in a position to cite you for the mandatory works.

Answer 8

Electricity goes to earth by a wire and not by you.
Blue - neutral
Brown - live and fuse
yellow/green - earth

Someone post the old colour code.
Red and black?

Answer 9

If you mean grounded, in theory electricity starts in the ground and has to return to the ground to make a complete circuit.

Answer 10

if not one gets electrocuted because it starts for earth and end up in the earth to complete the circuit.