ABB RELION REX640 Technical Manual page 577

1MRS759142 F
ROVPTOV, START -output
TONGAPC, Q1 -output
MFADPSDE, BLOCK -input, inversed
MFADPSDE, START -output
MFADPSDE, OPERATE -output
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.
The release delay should be based on known delays in resistor (re)connection:
• Logic OFF-ON-OFF:
• Logic ON-OFF-ON:
The resulting total protection operate time is defined as follows:
• Logic OFF-ON-OFF:
time of MFADPSDE.
• Logic ON-OFF-ON:
Operate delay time of MFADPSDE.
• Set
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
Reset timer is activated at the falling edge of GFC release, that is, when zero-
sequence voltage falls below
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
The estimated stabilized fundamental frequency residual current
the internally fixed threshold, which is 1% of In. This current magnitude threshold
supervision is based on the "Amplitude" method.
REX640
Technical Manual
TONGAPC: On delay time (ms)
In the configuration, equal
be used for ROVPTOV and MFADPSDE.
Switch on delay of the parallel resistor.
Switch off delay + Time off time of the parallel resistor.
Switch on delay of the parallel resistor + set Operate delay
Switch off delay + Time off time of the parallel resistor + set
Operate delay time of MFADPSDE smaller than the connection duration time
Reset delay time and Voltage start value must
Start delay time has elapsed.
Voltage start value . BLK_EF is reset once the reset
Directional mode setting
Protection functions
1
I
exceeds
o stab
577