How to calculate the NGR value for a 2.7MVA Transfomer,
11KV system where the fault current has to be limited to
50A?

Answer Posted / pavan

The value of the NGR to be inserted in the cicuit can be
calculated by the simple formula

R = V / (√3 * I)

Where V is the System Line voltage in Volts
I is the value of the fault current to be limited in your
case it is 50A.

In general practice the fault current is limited to the
full load rating of the largest equipment available in the
system.

Is This Answer Correct ?    6 Yes 4 No



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