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
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)
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 15 mA sec. (I
rated
 = 1 A) or
75 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
I
2nd harm
 = 5 mA sec. (I
rated
 = 1 A) or
I
2nd harm
 = 25 mA sec. (I
rated
 = 5 A)
Frequency Operating Range
0.9 ≤ f/f
rated
 ≤ 1.1 According to specified tolerances
10 Hz ≤ f < 0.9 f
rated
1.1 f
rated
 < f ≤ 90 Hz
Slightly expanded tolerances
f < 10 Hz
f > 90 Hz
Inactive
12.11
Technical Data
12.11 Inrush-Current Detection
SIPROTEC 5, Merging Unit 6MU85, Manual 845
C53000-G5040-C074-1, Edition 01.2020