Siemens 7SR45 Argus User Manual page 32

Table 3-5
Curve type
IEC-NI 0.14
IEC-VI 13.5
IEC-EI 80
IEC-LTI 120
IEEE/ANSI - MI ----
IEEE/ANSI - VI ----
IEEE/ANSI - EI ----
Where,
I - Fault current Magnitude
Is - Pickup setting
Tm - Time multiplier
Table 3-6
Parameters Description
Gn 51N-n Element 51N-n Block
Gn 51N-n Setting Pick-up current
Gn 51N-n Char Characteristics
Time Multiplier
Gn 51N-n Time
Mult
(other than DTL)
Delay
Gn 51N-n Delay (Applicable only for
DTL)
Gn 51N-n Min Minimum Operate
Operate Time
Gn 51N-n
Follower DTL
Follower DTL
Gn 51N-n Reset Reset
©2018 Siemens Protection Devices Limited
Constants for operating and reset curve characteristics
Operating time
K α P
0.02 ----
1.0 ----
2.0 ----
1.0 ----
---- 0.02
---- 2.0
---- 2.0
Time Delayed Derived Earth Fault Protection (51N-n)
Default
Value
Disabled
0.5xI
IEC NI
1
5 s
0 s
0 s
0 s
Chapter 1 - 7SR45 Description of Operation
A B
---- ----
---- ----
---- ----
---- ----
0.0515 0.114
19.61 0.491
28.2 0.1217
Min Max
- -
0.1xI 0.8xI
n n n
- -
0.01 10
0 s 15 s
0 s 20 s
0 s 20 s
60, IEC/
0 s ANSI
DECAY
Reset time
R n
9.7 2
43.2 2
58.2 2
80 2
4.85 2
21.6 2
29.1 2
Step Change
-
0.01
-
0.01
0.01
0.01
0.01
1
Chapter 1 Page 29 of 48