GE C60, Instruction Manual

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GE Multilin C60 Breaker Protection System 5-227
5 SETTINGS 5.7 CONTROL ELEMENTS
5
loss of guard frequency, or a remote transfer trip signal is received. When the pause signal disappears the autoreclose
cycle is resumed. This feature can also be used when a transformer is tapped from the protected line and a reclose is
not desirable until it is disconnected from the line. In this situation, the reclose scheme is
paused until the transformer
is disconnected.
• AR INCOMPLETE SEQ TIME : This timer is used to set the maximum time interval allowed for a single reclose shot. It
is started whenever a reclosure is initiated and is active until the
CLOSE BKR1
or
CLOSE BKR2
signal is sent. If all con-
ditions allowing a breaker closure are not satisfied when this time expires, the scheme goes to “Lockout”. The mini-
mum permissible setting is established by the
AR 3-P DEAD TIME 2
timer setting. Settings beyond this will determine the
wait time for the breaker to open so that the reclose cycle can continue and/or for the
AR PAUSE
signal to reset and
allow the reclose cycle to continue and/or for the
AR BKR1 BLK
signal to disappear and allow the
AR CLOSE BKR1
signal
to be sent.
• AR BLOCK BKR2 : This input selects an operand that will block the reclose command for breaker 2. 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 BKR2 : This setting represents the closing time for the breaker 2 from the moment the 'Close' com-
mand is sent to the moment the breaker contacts are closed in the "Protection AND CB" mode or when Open Pole is
reset in the "Protection only" mode. In the "Protection Only" mode,
AR1 CLOSE BRK 1
is reset if either protection oper-
ates again in the case of the unsuccessful reclose attempt or the breaker closes successfully, indicated by the Open
Pole reset within a 150 ms window after the close command is issued. Therefore it is important to set
AR CLOSE TIME
BRK1
time greater than the maximum expected breaker close time plus at least 150 ms with a "Protection AND CB"
mode.
• AR TRANSFER 1 TO 2 : This setting establishes how the scheme performs when the breaker closing sequence is 1-2
and breaker 1 is blocked. When set to “Yes” the closing command will be transferred direct to breaker 2 without waiting
the transfer time. When set to “No” the closing command will be blocked by the
AR BKR1 BLK
signal and the scheme
will be sent to lockout by the incomplete sequence timer.
• AR TRANSFER 2 TO 1 : This setting establishes how the scheme performs when the breaker closing sequence is 2-1
and breaker 2 is blocked. When set to “Yes” the closing command will be transferred direct to breaker 1 without waiting
the transfer time. When set to “No”, the closing command will be blocked by the
AR BKR2 BLK
signal and the scheme
will be sent to lockout by the incomplete sequence timer.
• AR BKR1 FAIL OPTION : This setting establishes how the scheme performs when the breaker closing sequence is 1-
2 and Breaker 1 has failed to close. When set to “Continue” the closing command will be transferred to breaker 2 which
will continue the reclosing cycle until successful (the scheme will reset) or unsuccessful (the scheme will go to Lock-
out). When set to “Lockout” the scheme will go to lockout without attempting to reclose breaker 2.
• AR BKR2 FAIL OPTION : This setting establishes how the scheme performs when the breaker closing sequence is 2-
1 and Breaker 2 has failed to close. When set to “Continue” the closing command will be transferred to breaker 1 which
will continue the reclosing cycle until successful (the scheme will reset) or unsuccessful (the scheme will go to Lock-
out). When set to “Lockout” the scheme will go to lockout without attempting to reclose breaker 1.
• AR 1-P DEAD TIME : Set this intentional delay longer than the estimated de-ionizing time after the first single-pole trip.
• AR BREAKER SEQUENCE : This setting selects the breakers reclose sequence: Select “1” for reclose breaker 1 only,
“2” for reclose breaker 2 only, “1&2” for reclose both breakers simultaneously, “1-2” for reclose breakers sequentially;
Breaker 1 first, and “2-1” for reclose breakers sequentially; Breaker 2 first.
• AR TRANSFER TIME : The transfer time is used only for breaker closing sequence 1-2 or 2-1, when the two breakers
are reclosed sequentially. The transfer timer is initiated by a close signal to the first breaker. The transfer timer trans-
fers the reclose signal from the breaker selected to close first to the second breaker. The time delay setting is based on
the maximum time interval between the autoreclose signal and the protection trip contact closure assuming a perma-
nent fault (unsuccessful reclose). Therefore, the minimum setting is equal to the maximum breaker closing time plus
the maximum line protection operating time plus a suitable margin. This setting prevents the autoreclose scheme from
transferring the close signal to the second breaker unless a successful reclose of the first breaker occurs.
• AR BUS FLT INIT : This setting is used in breaker-and-a-half applications to allow the autoreclose control function to
perform reclosing with only one breaker previously opened by bus protection. For line faults, both breakers must open
for the autoreclose reclosing cycles to take effect.