Sel SEL-351S - Figure 3.9 Levels 5-6 Neutral Ground Instantaneous Overcurrent Elements

3.11
Date Code 20080103 Instruction Manual SEL-351S Relay
Overcurrent, Voltage, Synchronism Check, Frequency, and Power Elements
Instantaneous/Definite-Time Overcurrent Elements
Figure 3.9 Levels 5–6 Neutral Ground Instantaneous Overcurrent Elements
Settings Ranges
Setting range for pickup settings 50N1P–50N6P:
0.250–100.00 A secondary (5 A nominal channel IN current input)
0.050–20.00 A secondary (1 A nominal channel IN current input)
0.005–2.500 A secondary (0.2 A nominal channel IN current input)
0.005–1.500 A secondary (0.05 A nominal channel IN current input)
NOTE: If channel IN is rated 0.2 A
nominal or 0.05 A nominal, then there
is an additional 2-cycle time delay on
all the neutral ground instantaneous
(50N1–50N6, 67N1–67N6) and
definite-time (67N1T–67N4T)
elements. Any time delay provided by
the definite-time settings (67N1D–
67N4D) is in addition to this 2-cycle
time delay.
Setting range for definite-time settings 67N1D–67N4D:
0.00–16000.00 cycles, in 0.25-cycle steps
Setting range for definite-time setting 67N2SD (used in DCB logic):
0.00–60.00 cycles, in 0.25-cycle steps
Accuracy
Pickup and Reset Time Curves
See Figure 3.5 and Figure 3.6.
Residual Ground
Instantaneous/
Definite-Time
Overcurrent Elements
Four levels of residual ground instantaneous/definite-time overcurrent
elements are available. Two additional levels of residual ground instantaneous
overcurrent elements (Levels 5 and 6) are also available. The different levels
are enabled with the E50G enable setting, as shown in Figure 3.10 and
Figure 3.11.
5ON5
5ON6
Relay
Word
Bits
50N5P
50N6P
I
N
Settings
Enabled
Levels
Level 5
Setting
E5ON ≥ 5)
Level 6
Setting
E5ON = 6)
Pickup: ±0.05 A secondary and ±3% of setting
(5 A nominal channel IN current input)
±0.01 A secondary and ±3% of setting
(1 A nominal channel IN current input)
±1 mA secondary and ±3% of setting
(0.2 A nominal channel IN current input)
±1 mA secondary and ±5% of setting
(0.05 A nominal channel IN current input)
Timer: ±0.25 cycles and ±0.1% of setting
Transient Overreach: ±5% of setting