ABB RELION REX640 Technical Manual page 1211

1MRS759142 F
Ph capacitive React
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SCEFRFLO can also determine the value for the
measurements. The calculation of
signal connected to the TRIGG_XC0F input when an earth-fault test is conducted
outside the protected feeder during commissioning, for example, at the substation
busbar. The
TRIGG_XC0F triggering input, the calculated value for setting
is obtained from recorded data as parameter
manually entered for the
the current switching state of the feeder so if the switching state of the protected
feeder changes, the value should be updated.
Figure 691
setting
Figure 691: An example configuration, which enables the measurement of setting Ph capacitive React
If the earth fault is detected by the residual overvoltage function ( START of
ROVPTOV), but not seen by the forward-looking earth-fault protection function
( START of DEFLPDEF), the fault is located outside the protected feeder. This
is mandatory for valid measurement of setting
delay (TONGAPC), the input TRIGG_XC0F is activated and the parameter
in the recorded data is updated. The delay (TONGAPC) must be set longer than
the start delay of the directional earth-fault function DEFLPDEF, but shorter than
the minimum operating time of the directional earth-fault functions in any of the
feeders. For example, if the start delay is 100 ms and the shortest operating time
300 ms, a value of 300 ms can be used. Circuit breaker and disconnector status is
used to verify that the entire feeder is measured.
Modeling a non-homogeneous line
A typical distribution feeder is built with several different types of overhead lines
and cables. This means that the feeder is electrically non-homogeneous. SCEFRFLO
allows the modeling of the line impedance variation in protection relay with three
line sections with independent impedance settings. This improves the accuracy of
REX640
Technical Manual
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=
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ef
Phase-to-earth voltage
Calculation Trg mode has to be "External". After the activation of the
Ph capacitive React setting. The calculated value matches
shows an example configuration, which enables the measurement of
Ph capacitive React .
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Ph capacitive React setting by
Ph capacitive React is triggered by the binary
XC0F Calc . This value has to be
Ph capacitive React . After a set
Protection related functions
(Equation 311)
Ph capacitive React
XC0F Calc
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