Schweitzer Engineering Laboratories SEL-421-4 - Table 5.46 OOS Logic Relay Settings

5.52
SEL-421 Relay Instruction Manual Date Code 20171021
Protection Functions
Out-of-Step Logic (Conventional)
➤ Setting R1L6 must be set greater than R1L7.
➤ Setting X1T6 must be set less than X1T7.
➤ Setting X1B6 must be set greater than X1B7.
➤ The minimum separation between settings R1R6 and R1R7 is 0.25/I
NOM
.
➤ The minimum separation between settings R1L6 and R1L7 is 0.25/I
NOM
.
➤ The minimum separation between settings X1T6 and X1T7 is 0.25/I
NOM
.
➤ The minimum separation between settings X1B6 and X1B7 is 0.25/I
NOM
.
➤ Setting OSBD must be greater than OSTD by a minimum of 0.5 cycle.
Table 5.46 OOS Logic Relay Settings
Setting Prompt Range
Default
(5 A)
EOOS Out-of-Step Y, Y1, N N
OOSB1 Block Zone 1 Y, N Y
OOSB2 Block Zone 2 Y, N Y
OOSB3 Block Zone 3 Y, N Y
OOSB4 Block Zone 4 Y, N N
OOSB5 Block Zone 5 Y, N N
OSBD
a
a
Hidden when EOOS = Y1.
Out-of-Step Block Time Delay (cycles) 0.500–8000 2.000
OSBLTCH
a
Latch Out-of-Step Blocking
b
b
The OSB (Out-of-Step Blocking) logic resets automatically after it asserts for more than 2
seconds. You can latch OSB if the power swing moves outside of Zone 6 before the two-second
timer expires.
Y, N N
EOOST Out-of-Step Trip Delay
c
c
Option I enables tripping on the way into Zone 6; option O enables tripping on the way out of
Zone 6; option N disabled OST (Out-of-Step Trip).
N, I, O, C N
OSTD
a
Out-of-Step Trip Delay (cycles) 0.500–8000 0.500
X1T7
a
Zone 7 Reactance—Top () (0.25–700)/I
NOM
23.00
X1T6
a
Zone 6 Reactance—Top () (0.25–700)/I
NOM
21.00
R1R7
a
Zone 7 Resistance—Right () (0.25–700)/I
NOM
23.00
R1R6
a
Zone 6 Resistance—Right () (0.25–700)/I
NOM
21.00
X1B7
a,d
d
Advanced Setting if EADVS := Y. If the Advanced Settings are not enabled (setting EADVS := N),
the relay hides the setting.
Zone 7 Reactance—Bottom () (–0.25–700)/I
NOM
–23.00
X1B6
a,d
Zone 6 Reactance—Bottom () (–0.25–700)/I
NOM
–21.00
R1L7
a,d
Zone 7 Resistance—Left () (–0.25–700)/I
NOM
–23.00
R1L6
a,d
Zone 6 Resistance—Left () (–0.25–700)/I
NOM
–21.00
50ABCP
d
Pos.-Seq. Current Supervision (A) (0.20–20) • I
NOM
1.00
50QUBP
a,d
Neg.-Seq. Current Supervision (A) (OFF, 0.10–20) • I
NOM
OFF
UBD
a,d
Neg.-Seq. Current Unblock Delay (cycles) 0.500–120 0.500
UBOSBF
a,d
Out-of-Step Angle Unblock Rate 1–10 4
OOSPSC No. of Pole Slips Before Tripping 1–10 1