ABB Relion REC670 - Page 63

Busbar
Protection
Busbar
1
2
2
1
en06000196.vsd
IED
1
IEC06000196 V2 EN-US
Figure 11: Example how to set CTStarPoint parameters in the IED
For busbar protection it is possible to set the CTStarPoint parameters in two ways.
The first solution will be to use busbar as a reference object. In that case for all CT inputs
marked with 1 in figure
11, set CTStarPoint = ToObject , and for all CT inputs marked with 2 in
figure 11, set CTStarPoint = FromObject .
The second solution will be to use all connected bays as reference objects. In that case for all
CT inputs marked with 1 in figure
11, set CTStarPoint = FromObject , and for all CT inputs
marked with 2 in figure 11, set CTStarPoint = ToObject .
Regardless which one of the above two options is selected busbar differential protection will
behave correctly.
The main CT ratios must also be set. This is done by setting the two parameters
CTsec and
CTprim for each current channel. For a 1000/1 A CT the following setting shall be used:
• CTprim = 1000 (value in A)
•
CTsec = 1 (value in A).
1MRK 511 358-UEN A Section 4
Analog inputs
57
Application manual