Answer / guru

The purpose of grounding the CT secondary is inorder to
protect the CT circuit in case of any earth fault in the CT
secondary circuit. Thus even there is an earth fault & the
CT is open the current will still circulates through the
ground to CT. It prevents the accidental open circuit in
the CT which may lead to develop a high potential in
secondary which may lead to CT blast.

Answer / mak

Only For the safety purpse the secondary is short circiuted.It it is open heavy current ll flow and damage the equipment

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