ABB RELION REX640 Technical Manual page 827

1MRS759142 F
blocks in this document. The configuration can be written to the protection relay
once the mismatch is corrected.
4.4.2.5 Operation principle
The function can be enabled and disabled with the
corresponding parameter values are "on" and "off".
The operation of DNSPDOC can be described with a module diagram. All the
modules in the diagram are explained in the next sections.
Figure 468: Functional module diagram
Level detector
The operating signal is compared to the set
exceeds the set
module. Timer starts when it is enabled and the directional criterion is fulfilled. A
suitable operating quantity can be selected with the
The options are "Negative seq" or "Residual". The value of operating quantity I_OPER
is also available in the Monitored data view.
Directional calculation
Directional calculation compares the negative-sequence current phasor with the
negative-sequence voltage phasor, that is, the polarizing quantity. The directional
operation can be selected with the
"Nondirectional", "Forward" or "Reverse" operation. By setting the value of
Non Dir to "True", the non-directional operation is allowed when the directional
information is invalid.
The
value of
direction are seen in the operating zone and all the faults in the opposite direction
are seen in the non-operating zone. The value of
the network configuration.
REX640
Technical Manual
I3P
IRES
U3P
BLOCK
Start value , Level detector sends an enabling signal to the Timer
Irrespective of the operating quantity selected, directional calculation is
always determined using the negative-sequence current.
Characteristic angle setting is used to turn the directional characteristics. The
Characteristic angle should be chosen so that all the faults in the operating
I
2
Level
Io
detector
U
2
Directional
calculation
Blocking
logic
Start value . If the operating signal
Directional mode setting. The options are
Characteristic angle depends on
Protection functions
Operation setting . The
Timer
OPERATE
t
START
Operating quantity setting.
Allow
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