en05000131.vsd
Time
Fault point
position
IEC05000131 V1 EN-US
Figure 344:
Inverse time overcurrent characteristics with inst. function
The inverse time characteristic makes it possible to minimize the fault clearance time
and still assure the selectivity between protections.
To assure selectivity between protections there must be a time margin between the
operation time of the protections. This required time margin is dependent of following
factors, in a simple case with two protections in series:
•
Difference between pickup time of the protections to be co-ordinated
•
Opening time of the breaker closest to the studied fault
•
Reset times of the protections
•
Margin dependent of the time delay inaccuracy of the protections
Assume we have the following network case.
Section 26
1MRK 511 408-UUS A
Inverse time characteristics
880
Phasor measurement unit RES670 2.2 ANSI
Technical manual
Summary of Contents for Relion RES670
Page 1: ...RELION 670 SERIES Phasor measurement unit RES670 Version 2 2 ANSI Technical manual ...
Page 2: ......
Page 276: ...270 ...
Page 306: ...300 ...
Page 360: ...354 ...
Page 406: ...400 ...
Page 614: ...608 ...
Page 732: ...726 ...
Page 748: ...742 ...
Page 884: ...878 ...
Page 932: ...926 ...
Page 933: ...927 ...