Answer / omar aziz

Resistive or high impedance earthing is classified as IT
system in IEC standards. It is employed where there is a
need to limit the earth fault current to minimium levels.

Primary this id the grounding techinique used in coal
minning where high earth fault currents can lead to
catastrophic fires.
I hope this helps. If yourequire further info there is a
good technical paper on schnider website,

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