ABB RELION REX640 Technical Manual page 720

Section 4
Protection functions
714
Connection of current transformers
The connections of the primary current transformers are designated as Type 1 and
Type 2.
• If the positive directions of the winding 1 and winding 2 protection relay currents
are opposite, the CT connection type is of "Type 1". The connection examples of
"Type 1" are as shown in figures
• If the positive directions of the winding 1 and winding 2 protection relay currents
equate, the CT connection type setting parameter is "Type 2". The connection
examples of "Type 2" are as shown in figures
• The default value of the CT connection type setting is "Type 1".
GUID-42CA1EAB-FC8C-4F99-912E-7264CFF2CAF3 V1 EN
Figure 393: Connection of current transformer of Type 1, example 1
393 and 394.
395 and 396.
1MRS759142 C
REX640
Technical Manual