Siemens SIPROTEC 7UT63 series - 4.5 Time Overcurrent Protection for Earth Current (Starpoint Current)

4.5 Time Overcurrent Protection for Earth Current (Starpoint Current)
453
7UT613/63x Manual
C53000-G1176-C160-2
4.5 Time Overcurrent Protection for Earth Current (Starpoint Current)
Characteristics
Current Stages
Definite-time stages DT I
E
>>, I
E
>
Inverse time stages
(acc. to IEC or ANSI)
IT I
EP
The same characteristics apply as for time
overcurrent protection for phase and residual
currents in accordance with the preceding
section
Reset characteristics
with disk emulation
IT The same reset time characteristics apply as
for time overcurrent protection for phase and
residual currents in accordance with the pre-
ceding section
High current stage I
E
>> 0.05 A to 35.00 A
1)
or ∞ (ineffective)
Steps 0.01 A
T
IE>>
0.00 s to 60.00 s
or ∞ (no trip)
Steps 0.01 s
Definite time current element
(50Ns-2, 50Ns-1)
I
E
> 0.05 A to 35.00 A
1)
or ∞ (ineffective)
Steps 0.01 A
T
IE>
0.00 s to 60.00 s
or ∞ (no trip)
Steps 0.01 s
Inverse current element (51Ns-
IEC)
I
EP
0.05 A to 4.00 A
1)
Steps 0.01 A
T
IEP
0.05 s to 3.20 s
or ∞ (no trip)
Steps 0.01 s
Inverse current element (51Ns-
ANSI)
I
EP
0.05 A to 4.00 A
1)
Steps 0.01 A
D
IEP
0.50 s to 15.0 s
or ∞ (no trip)
Steps 0.01 s
Tolerances with definite time
currents 3 % of setting value or 1 % nominal current
times 1 % of setting value or 10 ms
Tolerances with inverse time (IEC)
currents Pickup with
1.05 ≤ I/I
EP
≤ 1.15;
times
5% ± 15 ms
5% ± 45 ms
at f
N
= 50/60 Hz
for f
N
= 16.7 Hz
for 2 ≤ I/I
EP
≤ 20
and T
IEP
/s ≥ 1
Tolerances with inverse time (ANSI)
times
5% ± 15 ms
5% ± 45 ms
at f
N
= 50/60 Hz
for f
N
= 16.7 Hz
for 2 ≤ I/I
EP
≤ 20
and D
IEP
/s ≥ 1
The set times are pure delay times.
1)
Secondary values for I
N
= 1 A; for I
N
= 5 A the currents must be multiplied by 5.