I have come across selecting the Neutral CT for transformer (132kV/33kV) for 33kV side. CT ratio has been finalised but its highest voltage level and insulation class are to be decided yet. Please help
If the transformer's neutral connection to ground were somehow to become disconnected so that it is no longer at ground potential, you could under some conditions have full 33kV potential across the CT's insulation to its physically grounded base. It will need to withstand that voltage if you want to keep the "magic smoke" in it.
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