Schweitzer Engineering Laboratories SEL-351A - Table 3.8 Negative-Sequence Time-Overcurrent Element Settings

3.27
Date Code 20080213 Instruction Manual SEL-351A Relay
Overcurrent, Voltage, Synchronism Check, and Frequency Elements
Time-Overcurrent Elements
Settings Ranges
See Section 9: Setting the Relay for additional time-overcurrent element
setting information.
Accuracy
Pickup:
±0.05 A secondary and ±3% of setting
(5 A nominal phase current inputs, IA, IB, IC)
±0.01 A secondary and ±3% of setting
(1 A nominal phase current inputs, IA, IB, IC)
Curve Timing:
±1.50 cycles and ±4% of curve time for currents between (and including)
2 and 30 multiples of pickup
Table 3.8 Negative-Sequence Time-Overcurrent Element Settings
Setting Definition Range
51QP pickup 0.25–16.00 A secondary
(5 A nominal phase current inputs, IA, IB, IC)
0.05–3.20 A secondary
(1 A nominal phase current inputs, IA, IB, IC)
51QC curve type U1–U5 (US curves) see Figure 9.1–Figure 9.10
C1–C5 (IEC curves)
51QTD time dial 0.50–15.00 (US curves) see Figure 9.1–Figure 9.10
0.05–1.00 (IEC curves)
51QRS electromechanical
reset timing
Y, N
51QTC SEL
OGIC control
equation torque
control setting
Relay Word bits referenced in Ta ble 9.5 or set
directly to logical 1 (= 1)
a
a
SELOGIC control equation torque control setting (e.g., 51QTC) cannot be set directly to
logical 0.
Courtesy of NationalSwitchgear.com