Interposing Ct Selection Guide - Siemens 7SR242 Duobias Technical Manual

Interposing CT Selection Guide

Power Transformer Vector Group
Yy0, YNy0, Yyn0, YNyn0, Ydy0, Yndy0, Ydyn0, Yndyn0, Dz0
Yd1, YNd1
Yd1, YNd1 + Earthing Transformer
Yy2, YNy2, Yyn2 YNyn2, Ydy2, YNdy2, Ydyn2, Yndyn2, Dz2
Yd3, YNd3
Yd3, YNd3 + Earthing Transformer
Yy4, YNy4, Yyn4, YNyn4, Ydy4, YNdy4, Ydyn4, Yndyn4, Dz4
Yd5, YNd5
Yd5, YNd5 + Earthing Transformer
Yy6, YNy6, Yyn6, YNyn6, Ydy6, YNdy6, Ydyn6, Yndyn6, Dz6
Yd7, YNd7
Yd7, YNd7 + Earthing Transformer
Yy8, YNy8, Yyn8, YNyn8, Ydy8, YNdy8, Ydyn8, Yndyn8, Dz8
Yd9, YNd9
Yd9, YNd9 + Earthing Transformer
Yy10, Yny10, Yyn10, YNyn10, Ydy10, YNdy10, Ydyn10, Yndyn10,
Dz10
Yd11, Ynd11
Yd11, Ynd11 + Earthing Transformer
Dy1, Dyn1
Dy1, Dyn1 + Earthing Transformer
Dy3, Dyn3
Dy3, Dyn3 + Earthing Transformer
Dy5, Dyn5
Dy5, Dyn5 + Earthing Transformer
Dy7, Dyn7
Dy7, Dyn7 + Earthing Transformer
Dy9, Dyn9
Dy9, Dyn9 + Earthing Transformer
Dy11, Dyn11
Dy11, Dyn11 + Earthing Transformer
1. Y or y denotes an unearthed star connection on the HV or LV side of the transformer.
2. YN or yn denotes an earthed star connection on the HV or LV side of the transformer.
3. D or d denotes a delta connection on the HV or LV side of the transformer respectively.
4. Z or z denotes a zigzag connection of the HV or LV side of the transformer respectively
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HV Interposing LV Interposing CT
CT Selection Selection
Ydy0,0 Ydy0,0
Yd1,-30 Yy0,0
Yd1,-30 Ydy0,0
Ydy2,-60 Ydy0,0
Yd3,-90 Yy0,0
Yd3,-90 Ydy0,0
Ydy4,-120 Ydy0,0
Yd5,-150 Yy0,0
Yd5,-150 Ydy0,0
Ydy6,180 Ydy0,0
Yd7,150 Yy0,0
Yd7,150 Ydy0,0
Ydy8,120 Ydy0,0
Yd9,90 Yy0,0
Yd9,90 Ydy0,0
Ydy10,60 Ydy0,0
Yd11,30 Yy0,0
Yd11,30 Ydy0,0
Yy0,0 Yd11,30
Ydy0,0 Yd11,30
Yy0,0 Yd9,90
Ydy0,0 Yd9,90
Yy0,0 Yd7,150
Ydy0,0 Yd7,150
Yy0,0 Yd5,-150
Ydy0,0 Yd5,-150
Yy0,0 Yd3,-90
Ydy0,0 Yd3,-90
Yy0,0 Yd1,-30
Ydy0,0 Yd1,-30
Chapter 7 Page 11 of 64