Allen-Bradley Rockwell Automation 857 User Manual page 78

3-28
Protection Functions
857-UM001A-EN-P – July 2009
Table 3.16 – Parameters of the directional earth fault stages I
(cont.)
Parameter Value
IoRes
IoCap
Io >
Io >
Uo>
Uo
Curve
DT
IEC
IEEE
IEEE2
RI
PrgN
Type
DT
NI
VI
EI
LTI
Parameters
t>
k>
Mode ResCap
Sector
Undir
Offset
Sector Default = 88
ChCtrl
Res
Cap
DI1...32
VI1..4
InUse
-
Res
Cap
Unit Description
pu Resistive part of I (only when
0
"InUse"=Res)
pu Capacitive part of I (only when
0
"InUse"=Cap)
A Pick-up value scaled to primary value
pu Pick-up setting relative to the
parameter "Input" and the
corresponding CT value
% Pick-up setting for U
0
% Measured U
0
Delay curve family:
Definite time
Inverse time. See "Inverse Time
Operation".
Delay type.
Definite time
Inverse time. See "Inverse Time
Operation".
s Definite operation time (for definite
time only)
Inverse delay multiplier (for inverse
time only)
High impedance earthed nets
Low impedance earthed nets
Undirectional mode
° Angle offset (MTA) for RecCap and
Sector modes
±° Half sector size of the trip area on
both sides of the offset angle
Res/Cap control in mode ResCap
Fixed to Resistive characteristic
Fixed to Capacitive characteristic
Controlled by digital input
Controlled by virtual input
Selected submode in mode ResCap.
Mode is not ResCap
Submode = resistive
Submode = capacitive
>, I >> (67N)
0 0
Note
Set
Set
Set
Set
Set
Set
Set
Set
Set
Set