Operate and Dropout Characteristic Curves
You can select from the following operate and dropout characteristic curves:
Table 12-3 Standard Characteristic Curves to IEC
Normal inverse: type A See chapter 12.5.2 Stage with Inverse-Time Charac-
teristic Curve, Figure 12-1
Very inverse: type B
Extremely inverse: type C See chapter 12.5.2 Stage with Inverse-Time Charac-
teristic Curve, Figure 12-2
Long-time inverse: type B
Table 12-4 Standard Characteristic Curves to ANSI
Inverse: type C See chapter 12.5.2 Stage with Inverse-Time Charac-
teristic Curve, Figure 12-3
Short inverse
Long inverse See chapter 12.5.2 Stage with Inverse-Time Charac-
teristic Curve, Figure 12-4
Moderately inverse
Very inverse See chapter 12.5.2 Stage with Inverse-Time Charac-
teristic Curve, Figure 12-5
Extremely inverse
Definite inverse See chapter 12.5.2 Stage with Inverse-Time Charac-
teristic Curve, Figure 12-6
Extension of the Operating Time
Extension of the operate time during operation with
transformer inrush-current detection
Approx. 10 ms
Current Operating Range
Current range
At least one phase current ≥ setting value I
release
All phase currents ≤ setting value I
ph, max
Frequency Operating Range
0.9 ≤ f/f
rated
≤ 1.1 According to specified tolerances
10 Hz ≤ 0.9 f
rated
1.1 f
rated
< f ≤ 80 Hz
Slightly expanded tolerances
f < 10 Hz
f > 80 Hz
Inactive
Tolerances
Reference value = rated current
Pickup value Approx. 2 % of the setting value or
0.8 % of the absolute value
Operate time for 2 ≤ I/I threshold value ≤ 20 5 % of the setting value or
+ 2 % of the current tolerance or 30 ms
Dropout time for I/I threshold value ≤ 0.90 5 % of the setting value or
+ 2 % of the current tolerance or 30 ms
Reference value = pos. seq. current
Pickup value Approx. 2 % of the setting value
or 4 % of the absolute value
(I1 > 50 mA (I
rated
= 1 A) or 250 mA (I
rated
= 5 A))
Technical Data
12.20 Negative-Sequence Protection
1490 SIPROTEC 5, Overcurrent Protection, Manual
C53000-G5040-C017-8, Edition 07.2017