Siemens SIPROTEC 4 7UT6 Series Manual page 150

Functions
2.4 Time Overcurrent Protection for Phase and Residual Currents
•
For definite time overcurrent protection (phases):
Address 2111 or 2112 for pickup value I>>,
Address 2113 for delay time T I>>,
Address 2114 or 2115 for pickup value I>,
Address 2116 for delay time T I>;
•
For inverse time overcurrent protection (phases) acc. to IEC curves:
Address 2121 or 2122 for pickup value Ip,
Address 2123 for time multiplier T Ip;
•
For inverse time overcurrent protection (phases) acc. to ANSI curves:
Address 2121 or 2122 for pickup value Ip,
Address 2124 for time multiplier D Ip.
User-defined Characteristics
For inverse time overcurrent protection the user may define his own tripping and dropout characteristic. For
configuration in DIGSI a dialogue box appears. Enter up to 20 pairs of current value and tripping time value.
Die eingegebene Kennlinie kann in DIGSI auch grafisch dargestellt werden.
[ausloesekennl-260602-kn, 1, en_GB]
Figure 2-77
In order to be able to create a user-defined tripping characteristic, the following must be set during configura-
tion of the scope of functions in address 120 DMT/IDMT Phase, option User Defined PU (see Section
2.1.3.1 Setting
The value pairs refer to the setting values for current and time.
Since current values are rounded in a specific pattern before they are processed in the device, we recommend
to use exactly the same preferred current values you can find in
Table 2-7
= 1 to 1.94
Ι/Ι
p
1.00 1.50
1.06 1.56
1.13 1.63
1.19 1.69
1.25 1.75
1.31 1.81
1.38 1.88
150
Entry and visualisation of a user-specific trip characteristic with DIGSI - example
Notes). If you also want to specify the dropout characteristic, set User def. Reset.
Preferred values of standardized currents for User-defined trip characteristics
= 2 to 4.75
Ι/Ι
p
2.00 3.50
2.25 3.75
2.50 4.00
2.75 4.25
3.00 4.50
3.25 4.75
Table 2-7.
= 5 to 7.75
Ι/Ι
p
5.00 6.50
5.25 6.75
5.50 7.00
5.75 7.25
6.00 7.50
6.25 7.75
= 8 to 20
Ι/Ι
p
8.00 15.00
9.00 16.00
10.00 17.00
11.00 18.00
12.00 19.00
13.00 20.00
14.00
SIPROTEC 4, 7UT6x, Manual
C53000-G1176-C230-5, Edition 09.2016