ABB REX 521, Техническое справочное руководство, стандартные конфигурации

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1MRS751802-MUM REX 521
219
Protection Relay
Technical Reference Manual, Standard Configurations
Fig. 11.4.4.1.-1 Cross-country fault
Detection of a cross-country fault can be implemented by non-directional earth fault
protection. In a case where the fault current is lower than the start current level of
the overcurrent protection because of the fault resistance, the separated non-
directional high-set earth fault stage I
0
>> can be used for detecting the fault. With
this arrangement it is also possible to get clear indication of the fault type if the
settings are selected so that this protection stage will operate only in double earth
fault situations.
In H04 standard configuration the measurement channel I
0
for earth fault current
measurement is fixedly connected to the non-directional earth fault stages.
11.4.4.2. Auto-reclosure function
The auto-reclosure function can be implemented as described in the seventh
application example (Section 10.3. Outgoing feeder, Medium M02)
11.4.5. Connections
All the necessary settings for the connections and signal routings can be set via the
Relay Setting Tool or the local HMI.
11.4.5.1. Protection signal routing
The settings for the protection signal routing can be implemented as described in the
first application example (refer to Section 9.1. Outgoing feeder, Basic B01).
11.4.5.2. Indication and control connections
The connections for indication and control can be implemented as described in the
first application example (Section 9.1. Outgoing feeder, Basic B01), except the
signals for the open and close buttons that in this example are disconnected to free
the digital inputs for other functionality. Local control can be executed via the HMI
according to the instructions in
REX 521 Operator’s Manual (see Section 1.5.
Related documents).
EF in phase L2
EF in phase L3
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