GE L90 Instruction Manual page 277

5 SETTINGS
ZONE 1 EXTENT:
The Zone 1 extension philosophy here is to apply an overreaching zone permanently as long as the relay is ready to
reclose, and reduce the reach when reclosing. Another Zone 1 extension approach is to operate normally from an under-
reaching zone, and use an overreaching distance zone when reclosing the line with the other line end open. This philoso-
phy could be programmed via the Line Pickup scheme.
The "Extended Zone 1" is 0 when Autoreclose is in Lockout or Disabled and 1 when Autoreclose is in Reset.
1. When "Extended Zone 1" is 0, the distance functions shall be set to normal underreach Zone 1 setting.
2. When "Extended Zone 1" is 1, the distance functions may be set to Extended Zone 1 Reach, which is an overreaching
setting.
3. During a reclose cycle, "Extended Zone 1" goes to 0 as soon as the first
) and remains 0 until the recloser goes back to Reset.
COUNT > 0
USE OF SETTINGS:
The single-phase autoreclose settings are described below.
• AR MODE: This setting selects the Autoreclose operating mode, which functions in conjunction with signals received
at the initiation inputs as described previously.
• AR MAX NUMBER OF SHOTS: This setting specifies the number of reclosures that can be attempted before reclo-
sure goes to Lockout when the fault is permanent.
• AR BLOCK BKR1: This input selects an operand that will block the reclose command for Breaker 1. This condition
can be for example: breaker low air pressure, reclose in progress on another line (for the central breaker in a breaker
and a half arrangement), or a sum of conditions combined in FlexLogic™.
• AR CLOSE TIME BKR1:This setting represents the closing time for the Breaker 1 from the moment the "Close" com-
mand is sent to the moment the contacts are closed.
• AR BKR MAN CLOSE: This setting selects a FlexLogic™ operand that represents manual close command to a
breaker associated with the autoreclose scheme.
• AR BLK TIME UPON MAN CLS: The autoreclose scheme can be disabled for a programmable time delay after an
associated circuit breaker is manually commanded to close, preventing reclosing onto an existing fault such as
grounds on the line. This delay must be longer than the slowest expected trip from any protection not blocked after
manual closing. If the autoreclose scheme is not initiated after a manual close and this time expires the autoreclose
scheme is set to the Reset state.
• AR 1P INIT: This setting selects a FlexLogic™ operand that is intended to initiate single-pole autoreclosure.
• AR 3P INIT: This setting selects a FlexLogic™ operand that is intended to initiate three-pole autoreclosure, first timer
( ) that can be used for a high-speed autoreclosure.
AR 3P DEAD TIME 1
• AR 3P TD INIT: This setting selects a FlexLogic™ operand intended to initiate three-pole autoreclosure. second timer
( ) can be used for a time-delay autoreclosure.
AR 3P DEAD TIME 2
• AR MULTI-P FAULT: This setting selects a FlexLogic™ operand that indicates a multi-phase fault. The operand value
should be zero for single-phase to ground faults.
• BKR ONE POLE OPEN: This setting selects a FlexLogic™ operand which indicates that the breaker(s) has opened
correctly following a single phase to ground fault and the autoreclose scheme can start timing the single pole dead
time (for 1-2 reclose sequence for example, Breaker 1 should trip single pole and Breaker 2 should trip 3 pole).
The scheme has a pre-wired input that indicates breaker(s) status.
• BKR 3 POLE OPEN: This setting selects a FlexLogic™ operand which indicates that the breaker(s) has opened three
pole and the autoreclose scheme can start timing the three pole dead time. The scheme has a pre-wired input that indi-
cates breaker(s) status.
• AR 3-P DEAD TIME 1: This is the dead time following the first three pole trip. This intentional delay can be used for a
high-speed three-pole autoreclose. However, it should be set longer than the estimated de-ionizing time following the
three-pole trip.
• AR 3-P DEAD TIME 2: This is the dead time following the second three-pole trip or initiated by the
This intentional delay is typically used for a time delayed three-pole autoreclose (as opposed to high speed three-pole
autoreclose).
GE Multilin L90 Line Differential Relay
5.6 CONTROL ELEMENTS
signal is issued (
CLOSE BREAKER
AR 3P TD INIT
AR SHOT
5
input.
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