ABB RELION REX640 Technical Manual page 454

Protection functions
ENA_MULT
RCA_CTL
Figure 255: Functional module diagram
Level detector
The magnitude of the operating quantity is compared to the set
the magnitude of the polarizing quantity is compared to the set
If both the limits are exceeded, the level detector sends an enabling signal to the
timer module. When the
value has no effect and the level detection is purely based on the operating quantity.
If the ENA_MULT input is active, the
value Mult setting.
Typically, the ENA_MULT input is connected to the inrush detection function
INRHPAR. In case of inrush, INRPHAR activates the ENA_MULT input, which multiplies
Start value by the Start value Mult setting.
Directional calculation
The directional calculation module monitors the angle between the polarizing
quantity and operating quantity. Depending on the
polarizing quantity can be the residual voltage (measured or calculated) or the
negative sequence voltage. When the angle is in the operation sector, the module
sends the enabling signal to the timer module.
The minimum signal level which allows the directional operation can be set with the
Min operate current and Min operate voltage settings.
Pol quantity is set to "Zero. seq. volt", the residual current and residual voltage are
If
used for directional calculation.
Pol quantity is set to "Neg. seq. volt", the negative sequence current and negative
If
sequence voltage are used for directional calculation.
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Enable voltage limit setting is set to "False", Voltage start
Enable voltage limit setting is set to "True", the magnitude of the
If the
polarizing quantity is checked even if the
"Non-directional" or
Start value or Start value Mult setting if the product of
not accept the
these settings exceeds the
Timer
Level
detector
t
Directional
calculation
Blocking
logic
Start value setting is multiplied by the Start
Directional mode was set to
Allow Non Dir to "True". The protection relay does
Start value setting range.
Pol quantity setting, the
1MRS759142 F
OPERATE
t
START
FAULT_DIR
DIRECTION
Start value and
Voltage start value .
Technical Manual
REX640