ABB RELION REX640 Technical Manual page 1292

Protection related functions
When the phase angle criterion is used, the DIRECTION output indicates on which
operating sector the negative or residual power is measured.
Low-level blocking
For a reliable operation, signal levels should be greater than the minimum level. If
they are not greater than the minimum level, Timer is blocked.
In the "Neg. seq. volt." polarization selection using the
amplitude of the negative-sequence current is greater than the
value and the negative-sequence voltage amplitude is greater than the
voltage value, the Enable signal is sent to Timer.
In the "Zero seq. volt." polarization selection using
of the residual current is greater than the
voltage amplitude is greater than the
sent to Timer.
Timer
Once activated, the internal operating timer is started. The Timer characteristic
is according to DT. When Timer has reached the value of
the RELEASE output is activated. If a drop-off situation happens, that is, if the
operating current moves out of the operating sector or signal amplitudes drop
below the minimum levels, before
state is activated. If the drop-off continues for more than
deactivated.
Blocking logic
The binary input BLOCK can be used to block the function. The activation of the
BLOCK input deactivates RELEASE output and resets Timer.
5.15.6 Application
The neutral power directional element function DNZSRDIR improves the possibility
to obtain selective function of the overcurrent protection in meshed networks.
DNZSRDIR is used to block or release other overcurrent protection functions.
5.15.7 Signals
5.15.7.1 DNZSRDIR Input signals
Table 1223: DNZSRDIR Input signals
Name
I3P
IRES
U3P
URES
Table continues on the next page
1292
Min operate current value and residual
Min operate voltage value, the Enable signal is
Release delay time is exceeded, the Timer reset
Type Default
SIGNAL -
SIGNAL -
SIGNAL -
SIGNAL -
1MRS759142 F
Pol quantity setting, if the
Min operate current
Min operate
Pol quantity , if the amplitude
Release delay time ,
Reset delay time , Timer is
Description
Three-phase currents
Residual current
Three-phase voltages
Residual voltage
Technical Manual
REX640