Inrush-Current Detection
Setting Values
Operating limit I
max
0.030 A to 35.000 A
at I
rated
= 1 A
0.15 A to 175.00 A
at I
rated
= 5 A
Increments of 0.001 A
Increments of 0.01 A
Content 2nd harmonic
10 % to 45 %
Increments of 1 %
Duration of the crossblock function
0.03 s to 200.00 s
Increments of 0.01 s
Times
Operating times
Approx. 29 ms
Pickup
Harmonic: I
2nd harm
/I
1st harm
Setting value or at least
Protection-class current transformers
I
1st harm
= 10 mA sec.
and I
2nd harm
= 10 mA sec.
(I
rated
= 1 A)
I
1st harm
= 50 mA sec.
and I
2nd harm
= 50 mA sec.
(I
rated
= 5 A)
Instrument transformers
I
1st harm
= 1 mA sec.
and I
2nd harm
= 1 mA sec.
(I
rated
= 1 A)
I
1st harm
= 5 mA sec.
and I
2nd harm
= 5 mA sec.
(I
rated
= 5 A)
Dropout
The greater dropout differential (=
| pickup threshold – dropout threshold |
) of the following
criteria is used:
Dropout differential derived from the parameter
Dropout ratio
If this parameter is not available, a dropout ratio of 95 % applies for the overcurrent protection and a dropout
ratio of 105 % applies for the undercurrent protection.
Minimum absolute dropout differential
Protection-class current transformers
5 mA sec. (I
rated
= 1 A) or
25 mA sec. (I
rated
= 5 A)
Instrument transformers
0.5 mA sec. (I
rated
= 1 A) or
2.5 mA sec. (I
rated
= 5 A)
Harmonic: I
2nd harm
/I
1st harm
0.75 or
Protection-class current transformers
I
2nd harm
= 5 mA sec. (I
rated
= 1 A) or
I
2nd harm
= 25 mA sec. (I
rated
= 5 A)
Instrument transformers
I
2nd harm
= 0.5 mA sec. (I
rated
= 1 A) or
I
2nd harm
= 2.5 mA sec. (I
rated
= 5 A)
11.29
Technical Data
11.29 Inrush-Current Detection
SIPROTEC 5, Low-Impedance Busbar Protection, Manual
979
C53000-G5040-C019-C, Edition 04.2021