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Why Neutral is used in Electrical System?
Why Neutral is used in Electrical System?

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None of the earthing systems is basically bad. They all ensure safety of persons. Each system has its own advantages and disadvantages and the user must therefore be guided according to his needs, with the exception, however, of prescription or of standard or legislative bans. When designing an industrial network, a suitable neutral earth arrangement must be selected: The neutral can either be insulated, or it can be connected to earth. The use of an insulated neutral in an HV network has the advantage of ensuring operational continuity since it does not trip on the first fault, however the network capacitance must be such that an earth fault current is not likely to endanger personnel or damage equipment. On the other hand, an insulated neutral implies the following: – the risk of high overvoltages likely to favourize multiple faults, – the use of super insulated equipment, – compulsory monitoring of the insulation, – protection against overvoltages, which will become compulsory in the near future, – the need for complex, selective protection against earth faults which cannot usually be ensured by simple current-measuring relays. An earthedneutral generally implies mandatory tripping on the first fault, however: -it reduces overvoltages, – it provides a simple, reliable, selective means of protection, – it allows the use of equipment, and in particular cables, with lower insulation levels than for an insulated neutral. Between 1880 and 1920, transmission and distribution of electrical power took place in

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