Inverse Definite Minimum Time Earth Fault Overcurrent Function - ABB REG316 4 Series Operating Instructions Manual

REG 316*4 1MRB520049-Uen / Rev. F
3.5.27. Inverse definite minimum time earth fault overcurrent
function (I0-Invers)
A. Application
Overcurrent function with IDMT characteristic. A typical applica-
tion is as back-up for the E/F protection function, in which case it
measures 3 I
nally derived.
B. Features
Tripping characteristic according to British Standard 142
·
(see Fig.
c = 0.02 : normal inverse
c = 1
c = 2
DC component filter
·
harmonic filter
·
external 3 I
·
phase currents
wider setting range than specified in BS 142.
·
C. Inputs and outputs
I. C.t./v.t. inputs
·
II. Binary inputs
·
III. Binary outputs
·
·
IV. Measurements
·
either supplied from an external source or inter-
0
3.5.27.1):
: very inverse and long time earth fault
: extremely inverse.
signal or 3 I
0
Current
Blocking
Starting
Tripping
Neutral current.
ABB Switzerland Ltd
internally derived from the three
0
3-271