Basler BE1-CDS220, Instruction Manual

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12-16 Installation BE1-CDS220
P0001-08
09-21-00
With the appropriate transformer and CT connection information, the relay can automatically determine
the required compensation. The relay can accommodate any combination of transformer and CT
connection (wye, delta AB, or Delta AC). For more information, refer to Section 3, Input And Output
Functions, Input Current.
To cancel out the zero sequence current source inside the zone of protection, connect circuit 2 CTs in
wye and specify a ground source on the delta transformer winding. For more information, refer to
Section 1, General Information, Problem 5.
Phase, Residual, and
I
2
overcurrent elements can be connected to either CT circuit for backup
protection. For more information on applying overcurrent backup, refer to Section 8, Application.
Overcurrent neutral ground (
I
N
) operates on internally calculated residual (3I0) current.
For complete metering and independent backup protection, add a BE1-951 Overcurrent Protection
System with the BE1-CDS220 (refer to Figure 12-18 for a connection diagram). To add only metering to
the BE1-CDS220, connect a BE1-MMS100.
1
2
3
1
BE1-CDS220
B2
B5
B1
B3
B6
B4
I
C1
I
B1
I
A1
1
B10
B14
B12
B9
I
A2
I
B2
I
C2
B13
B11
3
2
4
H1 H2 H3
X1
X2
X3
DAC
Groundin
g Bank
3I0
4
3
4
5
Low Side Breaker
AØ
BØ CØ
Figure 12-19. Differential Protection for Wye-Grounded-Delta Transformer
with Ground Source inside the Protected Zone