Siemens siprotec 7SA522 - Page 451

4.5 Earth Fault Overcurrent Protection in Earthed Systems (optional)
451
7SA522 Manual
C53000-G1176-C155-3
Definite Time Overcurrent Stage
Inverse Time Overcurrent Stage (IEC)
Inverse Time Overcurrent Stage (ANSI)
Pickup value 3I
0
>for I
N
= 1 A 0.05 A to 25.00 A
or
0.003 A to 25.000 A
Increments 0.01 A
Increments 0.001 A
for I
N
= 5 A 0.25 A to 125.00 A
or
0.015 A to 125.000 A
Increments 0.01 A
Increments 0.001 A
Delay T
3I0>
0.00 s to 30.00 s
or ∞ (ineffective)
Increments 0.01 s
Dropout Ratio Approx. 0.95 for I/I
N
≥ 0.5
Pickup time
(1.5 set value)
(2.5 set value)
Approx. 45 ms
Approx. 35 ms
Dropout time Approx. 30 ms
Tolerances Current 3 % of setting value or 1 % nominal current
Time 1 % of setting value or 10 ms
The set times are pure delay times
Pickup value 3I
0P
for I
N
= 1 A 0.05 A to 25.00 A
or
0.003 A to 25.000 A
Increments 0.01 A
Increments 0.001 A
for I
N
= 5 A 0.25 A to 125.00 A
or
0.015 A to 125.000 A
Increments 0.01 A
Increments 0.001 A
Time factor T
3I0P
0.05 s to 3.00 s
or ∞ (ineffective)
Increments 0.01 s
Additional time delay T
3I0P verz
0.00 s to 30.00 s
or ∞ (ineffective)
Increments 0.01 s
Characteristics See Figure 4-1
Tolerances Current Pickup at 1.05 ≤ I/3I
0P
≤ 1.15
Time 5 % ± 15 ms for 2 ≤ I/3I
0P
≤ 20 and T
3I0P
/s ≥ 1
Pickup value 3I
0P
for I
N
= 1 A 0.05 A to 25.00 A
or
0.003 A to 25.000 A
Increments 0.01 A
Increments 0.001 A
for I
N
= 5 A 0.25 A to 125.00 A
or
0.015 A to 125.000 A
Increments 0.01 A
Increments 0.001 A
Time factor D
3I0P
0.50 s to 15.00 s
or ∞ (ineffective)
Increments 0.01 s
Additional time delay T
3I0P verz
0.00 s to 30.00 s
or ∞ (ineffective)
Increments 0.01 s
Characteristics See Figure 4-2 and 4-3
Tolerances Current Pickup at 1.05 ≤ I/3I
0P
≤ 1.15
Time 5 % ± 15 ms for 2 ≤ I/3I
0P
≤ 20 and D
3I0P
/s ≥ 1