ABB RELION REX640 Technical Manual page 1023

1MRS759142 F
Figure 568: Typical impedance locus in underexcitation: a) heavy load b) light load c)
fault in the network
4.7.3.7 Signals
UEXPDIS Input signals
Table 949: UEXPDIS Input signals
Name
I3P
U3P
BLOCK
EXT_LOS_DET
UEXPDIS Output signals
Table 950: UEXPDIS Output signals
Name
OPERATE
START
REX640
Technical Manual
X (Reactance)
-R
Relay operation
characteristics
Type
SIGNAL
SIGNAL
BOOLEAN
BOOLEAN
Type
BOOLEAN
BOOLEAN
c
a
a) Z locus in under excitation for heavily loaded machine
b) Z locus in under excitation for lightly loaded machine
-X
c) Z locus for a fault in the network
Default
-
-
0=False
0=False
Protection functions
R (Resistance)
b
Description
Three-phase currents
Three-phase voltages
Block signal for acti-
vating the blocking
mode
External signal for
excitation loss detec-
tion
Description
Operate
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