ABB RELION 670 Series Technical Manual page 396

Section 7
Impedance protection
Table 175: LEXPDIS (40) Non group settings (basic)
Name Values (Range)
GlobalBaseSel 1 - 12
MeasureMode PosSeq
AB
BC
CA
Table 176: LEXPDIS (40) Non group settings (advanced)
Name Values (Range)
InvertCTcurr No
Yes
7.12.6 Monitored data
Table 177: LEXPDIS (40) Monitored data
Name
XOHM
XPERCENT
ROHM
RPERCENT
7.12.7 Operation principle
The Loss of excitation (LEXPDIS ,40) protection in the IED measures the apparent impedance seen
out from the generator.The measurement loop of apparent impedance can be chosen as the
positive sequence loop or any one of the three phase-to-phase loops depending on the available
current and voltage signals. It is recommended to use positive sequence quantities for function
operation.
390
Unit Step
- 1
- -
Unit Step
- -
Type Values (Range)
REAL -
REAL -
REAL -
REAL -
Default Description
1 Selection of one of the Global Base Value
groups
PosSeq Measuring mode (PosSeq, AB, BC, CA)
Default Description
No Invert CT current
Unit Description
Ohm Reactance in Primary Ohms
% Reactance in percent of Zbase
Ohm Resistance in Primary Ohms
% Resistance in percent of Zbase
1MRK 502 066-UUS B
PID-3665-MONITOREDDATA v4
SEMOD156166-4 v6
Technical manual