combined differential and restricted earth fault scheme.

[Rugabamoses]

Guys,
I need to carry out this kind of scheme using star/delta auxilliary current transformers but am puzzled on how to specify the phase correcting auxilliary CTs. Can someone help me?

 

[davidbeach]

With modern numeric relays there is no need for aux CTs. The use of aux CTs is a hold over from the days of electromechanical relays and is best avoided if possible.

 

[slavag]

What David said.
Regards.
Slava