Why NGR is provided in sub station?
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Answer / jb
NGR means Neutral Grounding Resistance.it is used for limit the earth fault current.
generally the NGR earthing used upto the 11kv , Ac supply
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Answer / jithendra
NGR or Neutral Grounding Resistors are used to limit the ground fault current to a safe value in the event of earth fault. A NGR limits the earth fault current to a value which will be sufficient to operate protective relays and prevent unwanted fault damage.
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Answer / patni
Generator /Transformer neutral is grounded through resistor, called NGR (Neutral Grounding Resistor)which is used to limit the ground fault current to a safe value in the event of the earth fault. A NGR limits the earth fault current to a value which will be sufficient to operate protective relays and prevent equipment damage by excessive flow of fault current.
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Answer / arvind kumar
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