Ct Connections And Transformation Ratio Correction - ABB RELION REX640 Technical Manual

Section 4
Protection functions
4.3.2.7
618
is set to "Clk num 0", the resulting connection group "Yd0" is not a supported
combination. All the non-supported combinations of Winding 1 type, Winding 2 type
and Clock number settings result in the default connection group compensation that is
"Yy0".

CT connections and transformation ratio correction

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 setting parameter is "Type 1". The
connection examples of "Type 1" are as shown in
• 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
• The default value of the CT connection type setting is "Type 1".
Figure 342 and
Figure 344 and Figure 345.
1MRS759142 C
Figure 343.
REX640
Technical Manual