5-282
L90 Line Current Differential System
GE Multilin
5.7 CONTROL ELEMENTS
5 SETTINGS
5
•
The breaker status is open.
•
An elevated high frequency current condition occurs and the current subsequently drops out again.
The algorithm is illustrated in the state machine diagram shown below.
Figure 5–151: ALGORITHM ILLUSTRATION – STATE MACHINE TO DETECT RESTRIKE
In this way, a distinction is made between a self-extinguishing restrike and permanent breaker failure condition. The latter
can be detected by the breaker failure function or a regular instantaneous overcurrent element. Also, a fast succession of
restrikes will be picked up by breaker failure or instantaneous overcurrent protection.
The following settings are available for each element.
•
BREAKER RESTRIKE 1 FUNCTION
: This setting enable and disables operation of the breaker restrike detection ele-
ment.
•
BRK RSTR 1 BLOCK
: This setting is used to block operation of the breaker restrike detection element.
•
BREAKER RESTRIKE 1 SOURCE
: This setting selects the source of the current for this element. This source must
have a valid CT bank assigned.
•
BREAKER RESTRIKE 1 PICKUP
: This setting specifies the pickup level of the overcurrent detector in per-unit values
of CT nominal current.
•
BREAKER RESTRIKE 1 RESET DELAY
: This setting specifies the reset delay for this element. When set to “0 ms”,
then FlexLogic operand will be picked up for only 1/8th of the power cycle.
•
BRK RSTR 1 BRK OPEN
: This setting assigns a FlexLogic operand indicating the open position of the breaker. It must
be logic “1” when breaker is open.
•
BRK RSTR 1 OPEN CMD
: This setting assigns a FlexLogic operand indicating a breaker open command. It must be
logic “1” when breaker is opened, either manually or from protection logic.
•
BRK RSTR 1 CLS CMD
: This setting assigns a FlexLogic operand indicating a breaker close command. It must be
logic “1” when breaker is closed.
Capacitor bank
offline
Current
interruption
(overcurrent)
High-frequency
elevated current
Restrike detected:
OP state asserted
Breaker close
Breaker
close
Breaker
close
Capacitor bank
online
Current
interruption
(overcurrent)
Breaker open
command or breaker
open state
834768A1.CDR
Summary of Contents for UR Series L90
Page 652: ...A 16 L90 Line Current Differential System GE Multilin A 1 PARAMETER LISTS APPENDIX A A ...
Page 772: ...B 120 L90 Line Current Differential System GE Multilin B 4 MEMORY MAPPING APPENDIX B B ...
Page 802: ...C 30 L90 Line Current Differential System GE Multilin C 7 LOGICAL NODES APPENDIX C C ...
Page 812: ...D 10 L90 Line Current Differential System GE Multilin D 1 IEC 60870 5 104 APPENDIX D D ...
Page 824: ...E 12 L90 Line Current Differential System GE Multilin E 2 DNP POINT LISTS APPENDIX E E ...
Page 834: ...F 10 L90 Line Current Differential System GE Multilin F 3 WARRANTY APPENDIX F F ...
Page 846: ...xii L90 Line Current Differential System GE Multilin INDEX ...