Schweitzer Engineering Laboratories SEL-311C - Table 3.2 Distance Elements Settings

3.6
SEL-311C Relay Instruction Manual Date Code 20060320
Distance, Out-of-Step, Overcurrent, Voltage, Synchronism Check, and Frequency Elements
Distance Elements
for all phase faults and will not overreach on ground faults. See
SEL Application Guide AG96-16: Applying SEL Distance
Relays on Lines with Power Transformers or Open Delta VTs
for more information.
➤ Blocking reclose on three-phase faults. Relay Word bits MPPn
(Zone/Level n phase-to-phase compensator distance element)
and MABCn (Zone/Level n three-phase compensator distance
element) may be used to discriminate between phase-to-phase
and three-phase faults in the SEL
OGIC
®
control equation
79DTL (drive-to-lockout).
79DTL = MABC2 * !MPP2 …
Note that both three-phase and single-phase compensator
distance elements will operate for Phase A-B faults within the
protected zone since the three-phase element uses V
C
mem (V
C
memorized voltage) for polarizing.
Compensator distance and positive-sequence polarized distance may not be
applied at the same time. The user selects compensator distance with a “C”
suffix to the number of zones in the E21P setting (e.g., 3C is three zones of
compensator distance relaying).
Table 3.2 Distance Elements Settings
Mho Phase Distance Elements (Zones 1–4)
Enable Setting: E21P
Setting range for Mho Phase
Distance Elements (Z1P–Z4P):
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)
Minimum sensitivity is
controlled by the pickup of the supervising
phase-to-phase 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-to-Phase Current Fault Detectors (Zones 1–4)
Setting Range for
Phase-to-Phase Current
Fault Detectors (50PP1–50PP4)
a
:
a
If setting EADVS = N, settings 50PP2–50PP4 are at minimum values and are hidden.
0.50–170.00 A
P-P
secondary, 0.01 A steps
(5 A nominal)
0.10–34.00 A
P-P
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 3.20 and
Figure 3.21.