ABB RELION REX640, Техническое руководство, Страница: 577 / 1960

ROVPTOV, START -output
TONGAPC: On delay time (ms)
TONGAPC, Q1 -output
MFADPSDE, OPERATE -output
MFADPSDE, START -output
MFADPSDE, BLOCK -input, inversed
Figure 332: Logic to release MFADPSDE at the time of resistor (re)connection
The logic enables exact operate time of MFADPSDE elapsed from time of resistor
(re)connection.
In the configuration, equal
Reset delay time and Voltage start value must
be used for ROVPTOV and MFADPSDE.
The release delay should be based on known delays in resistor (re)connection:
• Logic OFF-ON-OFF:
Switch on delay of the parallel resistor.
• Logic ON-OFF-ON:
Switch off delay + Time off time of the parallel resistor.
The resulting total protection operate time is defined as follows:
• Logic OFF-ON-OFF:
Switch on delay of the parallel re set Operate delay
time of MFADPSDE.
• Logic ON-OFF-ON: Switch off delay + Time off time of the parallel re set
Operate delay time of MFADPSDE.
• Set
Operate delay time of MFADPSDE smaller than the connection duration time
of the resistor.
If earth faults are only alarmed, the external logic is not needed.
When the proposed logic is used and indication of transient earth faults is needed,
the
START
output from INTRPTEF can be used.
Timer
If the detected fault direction is opposite to the set directional mode and GFC
release is active,
BLK_EF
output is activated once
Start delay time has elapsed.
Reset timer is activated at the falling edge of GFC release, that is, when zero-
sequence voltage falls below
Voltage start value. BLK_EF is reset once the reset
delay time elapses. Activation of the
BLOCK
input deactivates the
BLK_EF
output
and resets Timer.
BLK_EF
output is activated when the following conditions are met:
• Earth fault is detected by the GFC
• Fault direction is opposite to
Directional mode setting
The estimated stabilized fundamental frequency residual current
I
o stab
1
exceeds
the internally fixed threshold, which is 1% of In. This current magnitude threshold
supervision is based on the “Amplitude” method.
1MRS759142 F Protection functions
REX640
Technical Manual
577