Answer / vinoth

Earth Connected to Neutral on Transformer Installation, Beacuse if Suppose fault current apper in circuit that time the current want to ground,If No Earth For Neutal Means it will affect the transformer windings only.

Answer / pradeep

In fact, transformer neutral is grounded for a star connected winding.
there are several reasons for neutral grounding in a transformer.
1. the main reason is to avoid automatic neutral shifting problem due to unbalanced loading.
2. Neutral can also be grounded to introduce the protections related to earth faults. So that the internal/external earth faults can be identified in the first instant in order to isolate the faulty circuit as faster as we can.
3. Neutral grounding can also be done through a series resistor/reactor or a transformer to limit the fault below certain level and to avoid the problem of "Arcing grounds"
4. Personal safety
5. Reduced magnitude of transient over voltages
And so on...!!

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