ABB 615 Series - Signals

impedance stays between the blinders for a predetermined time, the function declares a
power swing condition and asserts an output that can be used to block the distance
protection. However, if the impedance passes the inner blinder and exits on the other side
of the mho characteristics (that is, the resistive component of impedance has opposite sign
as at the time of point of entry) an out of step tripping is issued by the function.
Figure 344
gives an example of out of step detection.
X
-X
-R R
A
B
C
GUID-87E27B8C-02D6-4970-AF78-55E6ACB630F0 V1 EN
Figure 344: Example of out of step detection
The shaded region indicates a fault zone in a distance protection function. For curve A, the
impedance moves into the out of step zone and leaves slowly, indicating the occurrence of
a swing that quickly stabilizes. For curve B, the impedance moves slowly into the out of
step zone and exits the zone indicating that the network is becoming unstable. For curve
C, impedance rapidly moves into, and remains in, the fault zone indicating an actual fault
and not an out of step condition.
4.7.1.6 Signals
Table 596: 78 Input signals
Name
Type Default Description
V
1
SIGNAL 0.0 Positive phase sequence voltage
I
1
SIGNAL 0.0 Positive phase sequence current
I
2
SIGNAL 0.0 Negative phase sequence current
BLOCK BOOLEAN 0=False Block signal for activating the blocking mode
DISABLE BOOLEAN 0=False Disable input
1MAC059074-MB A Section 4
Protection functions
615 series ANSI 693
Technical Manual