Schweitzer Engineering Laboratories SEL-421-4 - Page 387

6.51
Date Code 20171021 Instruction Manual SEL-421 Relay
Protection Applications Examples
500 kV Parallel Transmission Lines With Mutual Coupling Example
Phase Instantaneous Overcurrent Pickup (Group)
50P1P Level 1 Pickup (OFF, 0.25–100 A secondary) 7.21
Phase Overcurrent Definite-Time Delay (Group)
67P1D Level 1 Time Delay (0.000–16000 cycles) 0.000
Phase Overcurrent Torque Control (Group)
67P1TC Level 1 Torque Control (SELOGIC Equation) 1
Selectable Operating Quantity Inverse-Time Overcurrent Element 1 (Group)
51S1O 51S1 Operating Quantity (IAn, IBn, ICn, IMAXn,
I1L, 3I2L, 3I0n)
a
3I0L
51S1P 51S1 Overcurrent Pickup (0.25–16 A secondary) 0.50
51S1C 51S1 Inverse-Time Overcurrent Curve (U1–U5) U3
51S1TD 51S1 Inverse-Time Overcurrent Time Dial (0.50–15) 1.68
51S1RS 51S1 Inverse-Time Overcurrent Electromechanical
Reset (Y, N)
Y
51S1TC 51S1 Torque Control (SEL
OGIC Equation) 32GF
Zone/Level Direction (Group)
DIR3 Zone/Level 3 Direction Control (F, R) R
Directional Control (Group)
ORDER Ground Directional Element Priority
(combine Q, V, I)
QV
E32IV Zero-Sequence Voltage And Current Enable
(SEL
OGIC Equation)
1
Pole-Open Detection (Group)
EPO Pole-Open Detection (52, V) 52
SPOD Single-Pole Open Dropout Delay (cycles) 0.500
3POD Three-Pole Open Dropout Delay (cycles) 0.500
POTT Trip Scheme (Group)
Z3RBD Zone 3 Reverse Block Time Delay (0.000–16000
cycles)
5.000
EBLKD Echo Block Time Delay (OFF, 0.000–16000 cycles) 10.000
ETDPU Echo Time Delay Pickup (OFF, 0.000–16000 cycles) 2.000
EDURD Echo Duration Time Delay (0.000–16000 cycles) 4.000
EWFC Weak Infeed Trip (Y, N, SP) N
27PWI Weak Infeed Phase Undervoltage Pickup
(1.0–200 V secondary)
47.0
27PPW Weak Infeed Phase-to-Phase Undervoltage Pickup
(1.0–300 V secondary)
80.0
59NW Weak Infeed Zero-Sequence Overvoltage Pickup
(1.0–200 V secondary)
5.0
PT1 General Permissive Trip Received
(SEL
OGIC Equation)
RMB1A
PT3 Three-Pole Permissive Trip Received
(SEL
OGIC Equation)
RMB2A
Table 6.13 Settings for 500 kV Parallel TX Example (Sheet 5 of 7)
Setting Prompt Entry