ABB REC670 Applications Manual page 185

1MRK 511 401-UUS A
Bay control REC670 2.2 ANSI
Application manual
ANSI05000149 V1 EN-US
Figure 70: Connection of polarizing voltage from an open (ANSI-broken) delta
The different steps can be described as follows.
Step 1
This step has directional instantaneous function. The requirement is that overreaching
of the protected line is not allowed.
3I
0
67
67N
N
ANSI05000150 V2 EN-US
Figure 71: Step 1, first calculation
Current protection
67N
xx05000149_ansi.vsd
One- or two-phase ground-fault
ANSI05000150_2_en.vsd
Section 8
M15282-123 v6
179