Schweitzer Engineering Laboratories SEL-311L, Instruction Manual, Page: 94 / 734

3-40 Line Current Differential, Distance, Out-of-Step, Overcurrent, Date Code 20011112
Voltage, Synchronism Check, and Frequency Elements
SEL-311L Instruction Manual
element may be selected from negative-sequence current or zero-sequence current if Advanced
Settings are enabled (Setting EADVS = Y).
Impedance Reach (Zones 1–4)
Enable Setting: E21MG Mho Ground
E21XG Quadrilateral Ground
Settings range for Mho elements (Z1MG
through Z4MG):
OFF, 0.05 to 64
Ω
sec, 0.01
Ω
steps
(5 A nominal)
OFF, 0.25 to 320
Ω
sec, 0.01
Ω
steps
(1 A nominal)
Settings range for Quadrilateral Reactance
elements (XG1 through XG4):
OFF, 0.05 to 64
Ω
sec, 0.01
Ω
steps
(5 A nominal)
OFF, 0.25 to 320
Ω
sec, 0.01
Ω
steps
(1 A nominal)
Settings range for Quadrilateral Resistance
elements (RG1 through RG4):
OFF, 0.05 to 50
Ω
sec, 0.01
Ω
steps
(5 A nominal)
OFF, 0.25 to 250
Ω
sec, 0.01
Ω
steps
(1 A nominal)
Minimum sensitivity is controlled by the pickup
of the supervising phase and residual overcurrent
elements for each zone.
Accuracy:
±
5% of setting at line angle for 30
≤
SIR
≤
60
±
3% of setting at line angle for SIR < 30
Transient Overreach: < 5% of setting plus steady-state accuracy
Phase and Residual Current Fault Detectors (Zones 1–4)
Setting Range for Phase and Residual Current
Fault Detectors (50L1 through 50L4 and
50GZ1 through 50GZ4):
Note: If EADVS = N, levels 2–4 fault
detectors are set at their minimum
values and are hidden.
0.50–100.00 Amps secondary, 0.01 A steps
(5 A nominal)
0.10–20.00 Amps secondary, 0.01 A steps
(1 A nominal)
Accuracy:
±
0.05 A and ±3% of setting (5 A nominal)
±
0.01 A and ±3% of setting (1 A nominal)
Transient Overreach: < 5% of pickup
Max. Operating Time: See pickup and reset time curves in Figure 3.43
and Figure 3.44.