Transformer Differential Relay Current Transformer Connections, 1992 Engineering Conference Proceedings
The connections for the delta and wye connected current transformers for power transformer differential relay circuits are dependent on the internal connections of the transformer to be protected. Transformers can be connected wye-delta or delta-wye, and with either the primary or secondary leading in either connection. If the wrong transformer diagram is used, the proper current transformer connections can not be determined. This paper demonstrates a procedure for identifying the connections of the transformer to be protected and for confidently determining all connections of the differential relay circuit current transformers.
Transformer Differential Relay Current Transformer Connections, 1992 Engineering Conference Proceedi